EPA/600/R-06/155 I July 2007 I www.epa.gov/ada
United States
Environmental Protection
Agency
Wetlands and Water
Quality Trading:
Review of Current Science and
Economic Practices with
Selected Case Studies
.-:
Ground Water and Ecosystems Restoration Division, Ada, Oklahoma 74820
National Risk Management Research Laboratory
Office of Research and Development
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EPA/600/R-06/155
July 2007
Wetlands and Water Quality Trading:
Review of Current Science and Economic
Practices With Selected Case Studies
Shane Cherry, Erika M. Britney, Lori S. Siegel, Michael J. Muscari, & Ronda L. Strauch
Prepared by Shaw Environmental Inc.
EPA Contract No. 68-C-03-097
Shaw Environmental Inc.
Cincinnati, Ohio 45212-2025
Timothy J. Canfield, Technical Monitor
U.S. Environmental Protection Agency
Office of Research and Development
National Risk Management Laboratory
Ada, Oklahoma 74820
Mary Sue McNeil, Project Officer
Ground Water and Ecosystems Restoration Division
National Risk Management Research Laboratory
Ada, Oklahoma 74820
National Risk Management Research Laboratory
Office of Research and Development
U.S. Environmental Protection Agency
Cincinnati, Ohio 45268
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Notice
The U.S. Environmental Protection Agency through its Office of Research and
Development funded and managed the research described here under contract
No. 68-C-03-097 to Shaw Environmental Inc. It has been subjected to the Agency's
peer and administrative review and has been approved for publication as an EPA
document. Mention of trade names or commercial products does not constitute
endorsement or recommendation for use.
All research projects making conclusions or recommendations based on en-
vironmental data and funded by the U.S. Environmental Protection Agency are
required to participate in the Agency Quality Assurance Program. This project did
not involve the collection or use of environmental data and, as such, did not require
a Quality Assurance Project Plan.
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Foreword
The U.S. Environmental Protection Agency is charged by Congress with protecting the Nation's land, air,
and water resources. Under a mandate of national environmental laws, the Agency strives to formulate
and implement actions leading to a compatible balance between human activities and the ability of natural
systems to support and nurture life. To meet this mandate, ERA'S research program is providing data
and technical support for solving environmental problems today and building a science knowledge base
necessary to manage our ecological resources wisely, understand how pollutants affect our health, and
prevent or reduce environmental risks in the future.
The National Risk Management Research Laboratory is the Agency's center for investigation of technologi-
cal and management approaches for preventing and reducing risks from pollution that threatens human
health and the environment. The focus of the Laboratory's research program is on methods and their
cost-effectiveness for prevention and control of pollution to air, land, water, and subsurface resources;
protection of water quality in public water systems; remediation of contaminated sites, sediments and
ground water; prevention and control of indoor air pollution; and restoration of ecosystems. NRMRL
collaborates with both public and private sector partners to foster technologies that reduce the cost of
compliance and to anticipate emerging problems. NRMRLs research provides solutions to environmental
problems by: developing and promoting technologies that protect and improve the environment; advanc-
ing scientific and engineering information to support regulatory and policy decisions; and providing the
technical support and information transfer to ensure implementation of environmental regulations and
strategies at the national, state, and community levels.
This publication has been produced as part of the Laboratory's strategic long-term research plan. It is
published and made available by EPA's Office of Research and Development to assist the user community
and to link researchers with their clients.
The goal of this report is to provide a review of the existing science and economic practices of using
wetlands as part of water quality trading programs. This report evaluates the technical, economic, and
administrative components of developing and implementing water quality trading (WQT) programs to nu-
trient removal is the primary focus to improve water quality. This report collates and synthesizes current
literature with the goal of providing a baseline understanding of the current state of the use of wetlands
in water quality trading programs. Although this document is intended to gather a significant amount
of the current scientific literature available at the time of publication, it should be noted that it does not
include all possible literature available on the subject due to the constantly evolving work in this area.
This document should be used as a component of all the science on this subject and not considered as
the sole document in this area.
•Stephen G. Schmelling, Director
Ground Water and Ecosystems/ftes/oration Division
National Risk Management Re^s§arch Laboratory
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Contents
Foreword iii
List of Figures ix
List of Tables x
Acronyms and Abbreviations xi
EPA Technical Oversight Committee xiii
Executive Summary xv
1.0 Introduction 1
1.1 What is Water Quality Trading? 1
1.2 Report Overview 1
2.0 Methods for Identifying Technical and Economic Analysis Needs 3
2.1 Literature Search Methodology 3
2.2 Literature Review Questions 4
2.2.1 Level 1 - Preliminary Screening Questions for Selection of Case Studies 4
2.2.2 Level 2 - Case Study Analysis Questions 5
2.2.3 Level 3 - General "State of the Art" Questions 5
2.3 Case Study Selection 5
3.0 Literature Review - Wetland Nutrient Removal 13
3.1 Wetland Removal of Nitrogen and Phosphorus - Technical Overview 13
3.2 Factors that Affect Nutrient Load Reduction Efficiencies 17
3.3 Natural versus Constructed Wetlands 18
3.3.1 Related Outcomes of Constructed Wetlands 19
3.4 Modeling Nitrogen and Phosphorus Removal by Wetlands 22
3.5 Defining Nutrient Load Reduction Credits 25
3.5.1 Measuring Nutrient Removal Performance 26
3.5.2 Modeling and Calculating Nutrient Removal 27
3.5.3 Assessing and Verifying Performance 28
3.5.4 Determining the Useful Life of Credits 28
4.0 Economic Literature Review 29
4.1 What Factors Determine the Cost of Creating a Market? 30
4.1.1 Concept Review and Approval Cost 31
4.1.2 Baseline Assessment Cost 31
4.1.3 Regional Water Quality Objective Costs 31
4.1.4 Allowance Allocation Cost 31
4.1.5 Market Development Cost 32
4.1.5.1 Creating the Exchange 32
4.1.5.2 Creating Demand 32
4.1.5.3 Creating Supply 33
4.1.5.4 Creating Pricing Structure 34
4.1.6 Acceptable BMP Cost 35
4.1.7 Stakeholder Communication Cost 35
4.2 What Factors Determine the Cost of Creating a Credit? 35
4.2.1 Project Initiation Cost 35
4.2.2 BMP Selection Cost 35
4.2.3 Approval and Permitting Cost 36
4.2.4 BMP Implementation Cost 36
4.2.5 BMP Monitoring Costs 37
4.3 What Factors Determine the Dollar Value of a Credit? 37
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4.3.1 Equivalence 37
4.3.2 Establishing Offset Fees 38
4.3.2.1 BMP Cost 38
4.3.2.2 BMP Effectiveness 38
4.3.2.3 Safety Factors 38
4.3.2.4 Administrative Factors 38
4.3.2.5 Trading Ratio 38
4.3.2.6 Offset Fee 39
4.3.3 Transaction Costs 39
4.3.3.1 Agency Transaction Costs 39
4.3.3.2 Trader Transaction Costs 39
4.3.4 The Asking Price 40
4.3.4.1 Minimum Selling Price 40
4.3.4.2 Seller Opportunity and Risk 40
4.3.5 The Bid Price 40
4.3.5.1 The Cost of Command-Control 41
4.3.5.2 The Cost of Alternative Strategies 41
4.3.5.3 Maximum Purchase Price 41
4.3.5.4 Value Created by Trading 42
4.3.5.5 Avoidance Strategy: Game the System 42
4.3.5.6 Buyer Risk Premium 42
4.3.6 Minimum Selling Price 42
4.3.6.1 BMP Cost 42
4.3.6.2 Seller Risk Premium 43
4.3.6.3 Profit 43
4.4 Challenges and Gaps 43
4.4.1 The Perspective Problem 43
4.4.2 Challenges to WQT 43
4.4.2.1 Simplified Modeling of Natural System Impacts 44
4.4.2.2 Expensive Risk Factors 44
4.4.2.3 High Transaction Costs 45
4.4.2.4 Undefined Property Rights 45
4.5 Potential Solutions 45
4.5.1 Regulatory Efficiency 45
4.5.2 PS Liability 46
4.5.3 Market Economic Valuation 46
4.5.4 Non-market Economic Valuation 47
4.5.5 Economic Investment Decision Methods 47
4.5.6 Probabilistic Analysis 48
4.5.7 System Dynamic Analysis 48
4.6 Conclusions and Recommendations 48
5.0 Trading Regulations Literature Review 50
5.1 USEPA Water Quality Trading Policy 51
5.2 Agricultural Policy Drivers for Using Wetlands in WQT 53
5.3 Regulations Related to Wetlands and Trading Programs 53
6.0 Case Study- Cherry Creek, Colorado 54
6.1 Overview 54
6.2 Background 55
6.3 Program Performance 55
6.4 Technical Performance 56
6.5 Economic Performance 58
6.6 Administrative Performance 59
6.7 Summary 59
7.0 Case Study - Minnesota River and Rahr Malting Company, Minnesota -
Rahr Malting Company Water Quality Trading: A Multifaceted Success 60
7.1 Overview 60
7.2 Background 61
7.3 Program Performance 61
7.4 Technical Performance 62
7.5 Economic Performance 65
7.6 Administrative Performance 66
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7.7 Summary 66
8.0 Case Study- Lower Boise River, Idaho 67
8.1 Overview 67
8.1.1 Location 67
8.1.3 Administration 68
8.2 Background 68
8.2.1 Phosphorus Movement 68
8.2.2 Trading 69
8.2.3 Regulations 69
8.2.4 Trading Framework 69
8.3 Program Performance 70
8.3.1 Trading Process 70
8.3.2 BMPs 71
8.3.3 Discount Factors 72
8.3.4 Calculating Credits 72
8.3.5 Example Trade 73
8.4 Summary 74
9.0 Case Study -Tar-Pamlico River and Neuse River, North Carolina 77
9.1 Tar-Pamlico Nutrient Reduction Trading Program 77
9.1.1 Background 78
9.1.2 Program Performance 79
9.1.3 Technical Performance 80
9.1.3.1 Methods for Defining Caps and Measuring Baseline Nutrient Loading 81
9.1.3.2 Methods for Quantifying Nutrient Load Reductions 81
9.1.4 Economic Performance 82
9.1.4.1 Calculating Offset Credit Value 82
9.1.4.2 Program Costs 83
9.1.5 Administrative Performance 83
9.1.5.1 Point Source Accountability 83
9.1.5.2 Nonpoint Source Accountability 84
9.2 Neuse River Basin Nutrient Sensitive Waters Management Strategy 84
9.2.1 Background 85
9.2.2 Program Performance 86
9.2.3 Technical Performance 86
9.2.3.1 Nutrient Removal by Constructed Wetlands 88
9.2.4 Economic Performance 89
9.2.4.1 Constructed Wetland Construction Costs 89
9.2.4.2 Program Costs 90
9.2.5 Administrative Performance 91
9.3 Summary 91
9.3.1 Unanswered Questions 92
10.0 Synthesis/Summary of Findings 93
10.1 Performance Monitoring versus Conservatism 93
10.2 Motivations for Nonpoint Source Participation 93
10.3 Effects of Compliance Thresholds and Enforcement 94
10.4 Comparison of Program Structure 94
10.5 Credit Life 94
10.6 Economic Challenges to Trading 94
10.7 Property Rights and Transfer of Liability 96
11.0 Research Recommendations 97
11.1 Technical Research Needs 97
11.1.1 Individual Wetland Performance 97
11.1.2 Watershed-Scale System Dynamics 98
11.2 Economic Research Needs 98
11.3 Regulatory and Administrative Research Needs 99
12.0 References 100
Appendix A Annotated Bibliography 110
VII
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Figures
Figure 6-1 The Cherry Creek Basin (CCBWQA, 2005) 54
Figure 6-2 Cherry Creek Basin with selected PRFs identified (CCBWQA, 2005) 58
Figure 7-1 The Minnesota River Basin 60
Figure 7-2 The Minnesota River Basin with sites of NPS sellers identified 64
Figure 8-1. Lower Boise, Idaho river watershed site map 67
Figure 9-1 Watersheds in North Carolina 77
Figure 9-2 Tar-Pamlico River Basin 79
Figure 9-3 Estimated TN concentration decrease using Seasonal Kendall test 80
Figure 9-4 Estimated TP concentration decrease using Seasonal Kendall test 80
Figure 9-5 Neuse River Basin 85
Figure 9-6 Neuse River NRCA performance, 1995 - 2004 87
Figure 9-7 Sources of Nitrogen in the Neuse River Basin (1995) 87
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Tables
Table 2-1. Internet Search Engines and Search Criteria 3
Table 2-2. Waterborne Stressor (Nutrient) Trading Programs 6
Table 4-1 Nitrogen Removal Cost-Effectiveness Comparison 36
Table 7-1 Pounds of Phosphorus and CBODs Reduced over Five Years 65
Table 7-2 Traded Units From Each Controlled Nonpoint Source 65
Table 8-1 Currently Eligible BMPs for Trading in LBR WQT Project 71
Table 8-2 Example Design of Sediment Basin and Wetland System 73
Table 8-3 Summary of Sediment Basin and Wetland System Simulation 74
Table 9-1 New Nutrient Removal Efficiencies for Stormwater BMPs Used Under the
Neuse and Tar-Pamlico Stormwater Rules 82
Table 9-2 Nitrogen Removal Cost-Effectiveness Comparison 83
Table 9-3 Summary of Construction Cost Curves, Annual Maintenance Cost Curves, and
Surface Area for Five Stormwater BMPs in North Carolina 90
Table 9-4 Cost Comparison of Four BMPs for 10-Acre Watershed (CN 80a) 90
Appendix A: Annotated Bibliography 111
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Acronyms and Abbreviations
|jg/L micrograms per liter
ACVWVA Arapahoe County Water and Wastewater Authority
ADAPT Agricultural Drainage and Pesticide Transport (model)
Association Tar-Pamlico Basin Association
ASWCD Ada Soil and Water Conservation District
CCBWQA Cherry Creek Basin Water Quality Authority
BMP best management practice
CBOD carbonaceous biological oxygen demand
CENR Committee on Environment and Natural Resources
cfs cubic feet per second
CH4 methane
CN curve number
CO2 carbon dioxide
CSCD Canyon Soil and Water Conservation District
CWA Clean Water Act
CZARA Coastal Zone Management Act Reauthorization Amendments
DCFROI discounted cash ow return on investment
DSWC Division of Soil and Water Conservation (North Carolina)
EEP Ecosystem Enhancement Program
ETN Environmental Trading Network
CIS geographic information system
GWERD Groundwater and Ecosystem Restoration Division
ICWC Idaho Clean Water Cooperative
IDAPA Idaho Administrative Procedures Act
IDEQ Idaho Department of Environmental Quality
ISCC Idaho Soil Conservation Commission
LAC local and basin committees
Ib/yr pound(s) per year
LBR Lower Boise River
LNBA Lower Neuse Basin Association
mg/L milligram(s) per liter
mgd million gallons per day
MOD Memorandum of Understanding
MPCA Minnesota Pollution Control Agency
MPP maximum purchase price
MSP minimum selling price
N2 nitrogen gas
N2O nitrous oxide
NADB North American Wetlands for Water Quality Data Base
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NANI net anthropogenic nitrogen inputs
NBOD nitrogenous biochemical oxygen demand
NCAC North Carolina Administrative Code
NCDWQ North Carolina Division of Water Quality
NCEDF North Carolina Environmental Defense Fund
NCEMC North Carolina Environmental Management Commission
NH4 ammonium
NH4-N ammonium nitrogen
NLEW Nitrogen Loss Evaluation Worksheet
NO3 nitrate
NO3-N nitrate-nitrogen
NOAA National Oceanic and Atmospheric Administration
NPDES National Pollutant Discharge Elimination System
NPS nonpoint source
NRCA Neuse River Compliance Association
NRCS Natural Resources Conservation Service
NRET Neuse River Education Team
NRMRL National Risk Management Research Laboratory
NSW nutrient sensitive waters
O&M operation and maintenance
PLAT Phosphorus Loss Assessment Tool
PRF Pollution Reduction Facility
PS point source
PTRF Pamlico-Tar River Foundation
Rahr Rahr Malting Company
RBC River Basin Center
SD standard deviation
SDA System Dynamics Analysis
Shaw Shaw Environmental, Inc.
SISL Surface Irrigation Soil Loss
SR-HC Snake River-Hells Canyon
SWAT Soil Water Assessment Tool
TD technical directive
TKN total Kjehldahl nitrogen
TMAL total maximum annual load
TMDL total maximum daily load
TN total nitrogen
TP total phosphorus
TSS total suspended solids
TWDB Treatment Wetland Database
USAGE U.S. Army Corps of Engineers
USDA U.S. Department of Agriculture
USEPA U.S. Environmental Protection Agency
WQT water quality trading
WTF wastewater treatment facility
WWTP wastewater treatment plant
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EPA Technical Oversight Committee
Timothy J. Canfield
Ecologist
U.S. EPA, ORD, NRMRL
919 Kerr Research Drive
Ada Ok 74820
Matt Heberling
Economist
U.S. EPA, ORD, NRMRL
26 W. M. L King Drive, MS A-130
Cincinnati, OH 45268
Kathy Hurld
Environmental Protection Specialist
U.S. EPA, OWOW, Wetlands Division
1200 Pennsylvania Avenue, NW
MCT 4502T
Washington, DC 20460
Michael Mikota
NNEMS Fellow
U.S. EPA - OWOW
1200 Pennsylvania Avenue, NW
MCT 4502T
Washington, DC 20460
Joseph P. Schubauer-Berigan
Research Ecologist
U.S. EPA, ORD, NRMRL
26WM. L.King Drive,
Cincinnati, OH 45268
Laurel Staley
Chief
Environmental Stressors Management Branch
U.S. EPA, ORD, NRMRL
26WM. L.King Drive,
Cincinnati, OH 45268
Richard Sumner
Regional Liason
U.S. EPA National Wetlands Program
200 SW 35th Street
Corvallis, OR 97333
Hale Thurston
Economist
U.S. EPA, ORD NRMRL
26WM. L.King Drive,
MS 499
Cincinnati, OH 45268
Cover Photo:
Clover Island - Restored wetland on a marginal
agricultural field. Blacksten Wildlife Area., Kent Co.
Delaware -T. Barthelmeh
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Shaw Author Affiliation
Shane Cherry
Shaw Environmental and Infrastructure, Inc.
19909 120th Avenue NE, Suite 101
Bothell, WA 98011-8233
Phone:425-218-9748
Shane.cherry@shawgrp.com
Erika M. Britney
Shaw Environmental and Infrastructure, Inc.
19909 120th Avenue NE, Suite 101
Bothell, WA 98011-8233
Phone: 425-402-3207
Erika.Britney@shawgrp.com
Lori S. Siegel
Siegel Environmental Dynamics, LLC
5 Carriage Lane
Hanover, NH 03755
Phone:603-643-1218
lsiegel.sed@comcast.net
Michael J. Muscari
ESA Adolfson
5309 Shilshole Ave. NW, Ste. 200
Seattle, WA 98107
Phone: 206-789-9658
Fax: 206-789-9684
mmuscari@adolfson.com
Ronda L. Strauch
King County Road Services Division
King Street Center, M.S. KSC-TR-0231
201 South Jackson Street
Seattle, WA 98104-3856
Phone:206-205-1561
Ronda.Strauch@METROKC.GOV
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Executive Summary
The Groundwater and Ecosystems Restoration Division of the National Risk Management Research
Laboratory serves as the U.S. Environmental Protection Agency's (USEPA) center for risk management
research on ecosystem protection and restoration. It provides detailed technical guidance through Technical
Directives (TD) for the technical review of papers, technical consultation, short-term project support, and
field support. The current assignment for Shaw Environmental, Inc. (Shaw) addressed by this technical
report is initiated by TD No. 2OA618SF and titled "Water Borne Stressor (Nutrient) Trading Program to
Improve Water Quality: Science and Economic Review."
The study evaluates the technical, economic, and administrative aspects of establishing water quality
trading (WQT) programs where the nutrient removal capacity of wetlands is used to improve water quality.
WQT is a potentially viable approach for wastewater dischargers to cost-effectively comply with regula-
tions and to improve water quality. The premise of WQT is that dischargers who cannot cost-efficiently
reduce their ef uent loads (i.e., high cost) may buy water quality from more cost-efficient (i.e., lower cost)
dischargers. Such trades may include point source (PS) dischargers, nonpoint source (NPS) discharg-
ers, or both. This study focuses on WQT programs that allow PS-NPS trades where wetlands are used
to achieve the NPS discharge reductions. The report integrates the review of published peer-reviewed
literature and data sources addressing the nutrient removal function of wetlands, WQT, and the review of
four case studies of existing WQT programs. Findings are used to illustrate opportunities and challenges
associated with using wetlands in NPS nutrient trades. Along with any resulting research, this study should
provide a technical basis for USEPA to prioritize research and publish related information resources.
The literature review addresses three concepts: (1) wetland nutrient removal, (2) trading economics, and
(3) trading regulations. The case studies investigate these concepts in practice. Criteria to select the
case studies included the type of program (PS-NPS); the constituent traded (nitrogen and phosphorus);
implementation status; whether or not wetland construction/enhancement could be used to generate
credits; and the extent to which published information was available on the program. Four case studies
are evaluated: (1) Cherry Creek, Colorado; (2) Minnesota River and Rahr Malting Company (Rahr), Min-
nesota; (3) Lower Boise River (LBR), Idaho; and (4) Tar-Pamlico and Neuse Rivers, North Carolina.
The first category of literature review evaluates wetland nutrient removal of nitrogen and phosphorus.
Constructed and natural wetlands are compared and contrasted. Both buffer downstream nutrients by
storing and transforming nutrients, thereby effectively treating discharge from PSs and NPSs.The fate and
transport of nutrients in wetlands is a function of dynamic biological, physical, and geochemical processes.
The resulting complexities render each wetlands application unique. As such, each application warrants an
evaluation of nutrient availability and the wetlands removal efficiency. Besides nutrient removal, wetlands
also provide several human and ecological benefits such as ood control, habitat for endangered and
economically important species, erosion control, and recreation. Caution must be exercised, though, to
avoid unintended consequences of constructed wetlands. Potential negative consequences include the
loss of other productive land uses, the impairment of adjacent water bodies, danger to wildlife attracted
to the wetland, in ux of invasive plants, odor issues, and in ux of dangerous or nuisance animals. In
order for wetlands to be used for WQT, it is necessary to be able to quantify the nutrient load reduction
to calculate tradable credits. Performance measurements or models/calculations of nutrient removal data
can be used to quantify these credits. The lifespan of the credits, which is a function of how long the best
management practice (BMP) is effective at removing nutrients, with a margin of safety, is also critical to
determining the value of the wetlands for a given trade.
Economics are examined as the second category of the literature review. WQT involves buyers, sell-
ers, and, to varying degrees, regulators. Each of these stakeholders has their own interests, concerns,
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challenges, and gaps. Special interests with diverse specific concerns and the general public also affect
economic decisions. There are several economic trading challenges that make the risk and/or return of
investing in WQT strategy unattractive to the stakeholder, thereby hindering efficient and fair deal-making
and ultimately suppressing WQT. These challenges include simplified modeling of natural system impacts,
expensive risk factors, high transaction costs, and undefined property rights.
Several changes to WQT program design could help overcome these obstacles by facilitating stakeholder
decision-making based on an improved understanding of value and risk. While some of the changes may
not necessarily increase the number of active trades, they all serve to improve the market so that trades
re ect intended goals. Measures to increase the efficiency of the trading programs would ultimately reduce
the cost to develop and operate WQT exchanges. They also reduce the transaction costs of individual
trades. Increasing PS compliance liability will provide a significant driver for trading. Improvements to
market and non-market economic valuations of ecological services must be achieved and would help
to increase the real or perceived value and opportunities NPSs can realize as a result of participating
in WQT. WQT would also benefit from making tools for applying economic investment decision methods
available to potential participants. Probabilistic analyses for evaluating the risk and opportunity associated
with WQT should replace single-point estimate inputs, which are subject to error and bias. Probabilistic
analysis would provide decision-makers with more confidence in committing capital to WQT. Finally, System
Dynamics Analysis (SDA), which is a modeling process that evaluates the consequences and sequencing
of complex events and phenomena inherent in many systems, would optimize the performance of the
WQT market. Many of these changes simply require modifications to existing policies and have proven
effective for other applications, such as business strategy development and resource management.
Finally, trading regulations are examined in the literature review. The report describes the USEPA Water
Quality Trading Policy, specifically examining regulations related to wetlands. In 2003, the USEPA released
its Water Quality Trading Policy to offer guidance and assistance in developing and implementing trad-
ing programs. Trading is particularly encouraged by the policy for phosphorus and nitrogen loads. The
geographic area for trading programs is described by the policy as the watershed or area covered by
an approved total maximum daily load (TMDL). Surplus credits are defined by the policy as constituent
reductions greater than those already required by a regulation. Clear authority to trade along with unam-
biguous legal protection for using the purchased credits to meet established regulatory requirements is
crucial for a successful WQT program. Success also mandates compliance and enforcement provisions.
Programs vary based on the location and circumstances of the trading and are thus administered by the
states. While strict limits on discharges drives demand for WQT, the 2007 Farm Bill will likely drive sup-
ply by compelling more NPS participation in trading. If supported by Congress, BMPs subsidized by tax
dollars will become eligible to generate sellable credits.
Four case studies are evaluated according to technical, economic, and regulatory concepts. The first of
these is the Cherry Creek, Colorado, case study, which is an example of a clearinghouse type of mar-
ket. In 1989, the Cherry Creek Reservoir Control Regulation, listed as Regulation #72, set the stage for
WQT between PS and NPS discharges of phosphorus and mandated the Cherry Creek Basin Water
Quality Authority (CCBWQA) to administer the basin. The CCBWQA has been dedicated to creating and
maintaining its own phosphorus reduction facilities. Furthermore, it has been committed to fostering and
evaluating other BMP sources in the watershed. Three trades have occurred, one of which involved an
NPS. Although these trades allowed PSs to offset some of their discharges more cost effectively, the
water quality goal has yet to be achieved because the TMDL was established to accommodate growth.
Nonetheless, with its exible trading approaches and unambiguous guidelines and oversight by the
CCBWQA, future success is possible.
The second case study, Rahr, in Minnesota, is an example of a sole-source offset accomplished without
an established market there. In 1997, the Minnesota Pollution Control Agency (MPCA) issued to Rahr
a discharge permit requiring WQT in order to satisfy the conditions of no additional oxygen-demanding
discharge into the Minnesota River Basin. The permit specified acceptable BMP options, which included
the three selected: critical area set-asides and wetland restoration, erosion control, and livestock exclu-
sion. The NPS controls achieved the offsets within four years and must be maintained as long as Rahr
discharges ef uent. The trades were necessary for Rahr's growth. The NPS controls implemented also
resulted in other environmental and economic benefits beyond improvements to water quality. Despite
the successes, limitations to the program's success exist. Instead of validating the performance of NPS
controls through monitoring, reductions were evaluated by conservative assumptions, thereby requiring
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larger water quality improvements from the BMP projects to compensate for uncertainty, and this added
expense. Furthermore, NPSs are not regulated and therefore do not have the same marketable incentive
to engage in trading. Rahr will have to overcome this in the event it needs to purchase additional credits.
Overall, the benefits far outweighed the limitations, rendering this trading program a success.
The third case study is the trading program in the LBR in Idaho. The Ef uentTrading Demonstration Project
is a start-up program for phosphorus trading in the LBR watershed in Idaho. Although the framework of
this exchange market has been established, the phosphorus TMDL has yet to be set, thereby delaying
the need for trades. Nonetheless, the WQT simulation of a scenario for generating credits used sediment
basins and constructed wetlands to reduce discharge. Unfortunately, high costs and use of resources to
develop the trading framework hinder the program. Water rights issues discouraged buyers and sellers from
participating. Potential regulation also deterred NPSs participation. Despite these issues, the participants
in the demonstration project felt that the LBR framework was successful. The project highlighted issues
of efficiency and uncertainties in credit calculations and BMP lifespan, and long-term fate of phosphorus
removed using BMPs such as constructed wetlands.
The fourth case study comes from the Tar-Pamlico and Neuse Rivers in North Carolina. Both of these
programs are based on a group cap-and-trade system and both rely on associations of PS dischargers.
A nutrient offset fee must be paid for each pound of nutrient discharged beyond that collectively allowed
for the association. This fee is paid to a state-administered fund for implementing BMPs to reduce the
nutrient load from NPSs. Both programs successfully implemented strategies to reduce nutrient loads.
The nutrient-sensitive water strategies for both basins relied heavily on public and stakeholder input.
While many lessons were learned, there remain many unanswered questions regarding issues such as
seasonality, nutrient removal efficiencies over time, and lifespan of the BMPs.
The literature review and case studies support a synthesis of the information regarding WQT involving
NPS reductions that utilize wetlands. This synthesis summarizes the key observations of the state of
WQT using wetlands based on examples provided by the case studies as well as warranted research and
modifications to encourage its viability. As a cautionary note, of the more than 80 WQT programs, pilots,
and simulations identified in the process of selecting the four case studies, these programs are among
the longest-standing. All were developed before the USEPA issued the Water Quality Trading Policy in
2003. It is therefore recommended that some of the most recent WQT programs, for which there is cur-
rently very little published data, be evaluated to determine how and to what extent these programs are
addressing the research needs and data gaps identified in this document. This said, the observations
made in this document include a comparison of performance monitoring versus conservative presump-
tion; motivations for NPS participation; effects of compliance thresholds; comparison of program structure;
credit life; economic challenges to trading; and property rights and transfer of liability.
Uncertainty drives the question of performance monitoring versus conservatism, whereby high trading
ratios are used to offset uncertainty. Such uncertainty derives from the dynamic, complex factors affect-
ing wetland nutrient removal efficiency and from spatial differences between the wetlands and the PS
location. Applying conservative safety factors often mitigates such uncertainty. The case studies illustrate
that typically program participants presume it is more cost-effective to apply such conservatism than to
directly measure the effectiveness of the constructed wetland.
WQT with NPS contributors depends on their desire to participate. The case studies demonstrate that
NPS nutrient loads often exceed PS loads to a watershed. WQT programs may be used to create an
economic incentive for NPSs to control their contributions by compensating them for load reductions.
This is feasible in certain circumstances based on the significant difference in costs. Unfortunately, NPS
contributors have a subtle disincentive to participate in trading programs in that they may lose their non-
regulated status or face stricter enforcement. Stronger incentives for NPS participation call for a better
understanding of nutrient loading on a watershed scale. Compliance thresholds directly affect trading
attractiveness. Discharge limits must be strict enough to oblige trading, while enforcement of these limits
must be credible to avoid dischargers from gaming the system instead of participating in trading.
Program structures vary considerably and include sole-source offsets, clearinghouses, and compliance
associations. The various models may all be valid when executed appropriately. Questions regarding
lifespan of BMPs concern the protocol beyond the expiration of credits, the temporal differences between
the times of credits generation and application, and the procedure to deal with surplus credits. Economic
trading challenges could suppress WQT by making the net economic value of trading less attractive than
xvii
-------
alternate compliance management strategies due to risks and uncertainties. These challenges could hinder
efficient and fair deal-making because they make the risk and/or return of investing in WQT high to the
buyer, the seller, or both. Lastly, the way property rights and liability transfer are addressed depends on
the program. Each of the case studies manages differently the question of liability in the event of BMP
failure. Lingering liability for the seller leaves unknown risk associated with trading plus additional costs,
and logistics associated with monitoring BMPs implemented on the credit seller's property make WQT
less attractive to PSs. Additionally, the property rights to a wetland after the credits have expired must
be clear. Such doubts deter the use of constructed wetlands as a BMP in WQT programs. Long-term
regulatory implications of building constructed wetlands to generate credits for WQT programs need to
be clarified.
Finally, additional research recommendations within technical, economic, and regulatory categories are
presented in the final section of this document. Technical research needs concern reducing uncertainty
in trades involving wetlands. Several possible research topics emerge to address uncertainty in wetland
performance. SDA can evaluate the complex events and phenomena inherent in many systems, thereby
reducing uncertainty and quantifying risk. To address economic challenges, research must aim to deter-
mine value and risk associated with strategies that use wetlands to reduce nutrient loads. Administrative
research targets regulations that promote opportunities, minimize transaction costs, formally supervise
WQT implementation and compliance, assess methods to promote NPS participation, and minimize
gaming risks.
WQT using wetlands is a potentially viable alternative for achieving water quality standards. This report
reviews the current technical, economic, and regulatory status of this option. Based on the observed
strengths and identified challenges, Shaw recommends actions to promote such programs to their full-
est potential.
XVIII
-------
1.0 Introduction
The Groundwaterand Ecosystems Restoration Division (GWERD) of the National Risk Management Research Labora-
tory (NRMRL) serves as the U.S. Environmental Protection Agency's (USEPA) center for risk management research on
ecosystem protection and restoration, focusing its efforts on studies to assess and enhance the ability of terrestrial and
aquatic ecosystems to support and maintain water quality, support native species of plants and animals, and to provide
ecological services on a watershed scale. Shaw Environmental, Inc. (Shaw) receives detailed technical guidance and
direction from NRMRL/GWERD in the form of Technical Directives (TD) for the areas of technical review of papers,
technical consultation, short-term project support, and field support. The current assignment addressed by this technical
report is initiated by TD No. 2OA618SF and titled "Water Borne Stressor (Nutrient) Trading Program to Improve Water
Quality: Science and Economic Review."
The relative importance of point sources (PS) and nonpoint sources (NPS) of nutrients varies from watershed to wa-
tershed. However, according to an agriculture handbook published by the U.S. Department of Agriculture (USDA), "na-
tional-scale water quality assessments strongly suggest that agriculture is a leading source of remaining water quality
problems" (Heimlich, 2003). Nutrient inputs into the waters of the United States continue to be one of the major reasons
that water bodies do not meet their designated uses as defined under the Clean Water Act (CWA; Federal Water Pollution
Control Act Amendments of 1972, later amended in 1977). USEPA instituted a Water Quality Trading Policy to encour-
age trading as an innovative way of meeting water quality goals within a watershed context (USEPA, 2003a). The policy
is based on the idea that different sources within a watershed may face drastically different costs to control the same
constituent. Trading programs, which have proved to be very successful in meeting air quality standards, allow facilities
facing higher discharge control costs to meet their regulatory obligations by purchasing environmentally equivalent, or
superior, reductions from another source at lower cost than they would incur by installing additional controls. To date,
this policy has been implemented to a limited extent for PS-PS trading. There is a great deal of interest in increasing the
implementation of this policy for PS-NPS trading, particularly through the use of wetlands (Schubauer-Berigan, 2005;
Raffini and Robertson, 2005), but there appear to be a number of possible gaps in the available scientific and economic
knowledge needed to implement such trading as part of a regulatory program.
1.1 What is Water Quality Trading?
Water quality trading (WQT) is a voluntary alternative for achieving regulatory compliance with water quality standards.
It is a program whereby parties can meet their discharge allowances by trading with each other. Although it has been
available for over two decades, this option is just recently garnering more attention. In WQT, cost-in efficient discharg-
ers1 buy water quality credits from cost-efficient dischargers, who have earned credits by voluntarily implementing best
management practices (BMPs) for nutrient control. By trading credits, the overall cost of achieving nutrient reduction is
minimized. In an efficient market, WQT leads to lowest-cost nutrient reduction.
An established market or exchange provides the structure for the WQT transactions. The regulator or some other entity
plays a third-party role in the market, protecting the interests of the public by ensuring that trading maintains or improves
water quality and does not lead to degradation of the environment.
Overall, economists, regulators, dischargers, environmentalists, and other stakeholders have advocated WQT as a
way to use market-based solutions to reduce the cost of complying with water quality discharge limits. The approach
provides PSs with alternatives for controlling discharges with less regulation, less cost, and accelerated compliance.
The exibility afforded by WQT that includes NPSs can create ecological value without increasing natural resource risk.
Regulatory oversight controls the process.
1.2 Report Overview
The initial work plan for the study included a broad assessment of published literature pertaining to WQT programs that
include NPS trades. As the study progressed, collaboration between the study sponsors and the authors focused the
scope of the study on the use of wetlands as an NPS control to reduce nutrient loads and create credits for trade.
1 In this document, "discharger" is a term used to refer to both PSs and NPSs whose discharge is due to human influences.
-------
The study evaluates the technical, economic, and administrative aspects of establishing WQT programs that can use
and have used wetlands to generate credits for NPS trades. The evaluation relies upon a review of technical literature
combined with selected case studies. The literature review and case studies are used to identify critical scientific and
economic knowledge gaps that would impede the implementation of a WQT program including both PSs and NPSs.
Although examples from several case studies facilitate specific points in the wetlands, economics, and regulatory re-
views, this report considers the four programs included as case studies to illustrate the current state of practice of using
wetlands in WQT programs. Although the programs described in the case studies are not markets, they are illustrative
of important aspects of WQT involving wetlands. Based on the synthesis of this work, the USERA will be able to develop
a plan to research gaps regarding using wetlands to generate NPS credits in WQT. Addressing these gaps will provide
insight towards assessing the feasibility of such programs and identify factors to opt for certain approaches.
-------
2.0 Methods for Identifying Technical and Economic Analysis Needs
The current investigation combines a review of published literature and a case study analysis to establish and evaluate
the state-of-the-art in WQT programs. By evaluating existing regionally focused WQT programs, the study identifies data
and knowledge gaps and recommends research to address them. Ultimately, this review and any resulting research
would enable USEPA to publish technical information for using wetlands in PS-NPS WQT programs. This study inte-
grates two primary components: (1) review of published peer-reviewed literature and data sources addressing WQT
and wetlands nutrient removal functions, and (2) review of four case studies of existing WQT programs. The literature
review and case study analysis results are used to assess opportunities and potential pitfalls associated with using
wetlands in NPS nutrient trades.
Shaw collaborated with USEPA to develop a list of critical questions to screen and compile relevant literature and other
available sources of information for the area of WQT programs for nutrients. The primary sources of information are
derived from published peer-reviewed literature, including articles from scientific and economic journals, conference
proceedings, and books. Other information sources include relevant federal and state regulations. Information gained
from secondary and non-peer-reviewed sources, including conference proceedings, workshops, white papers, fact
sheets, web sites, etc., is used to illustrate the level of interest in WQT.
The literature review will produce a list of issues pertaining to the successful operation of WQT programs along with
published data and a bibliography addressing each of these issues. The association of issues and available data will
illustrate the nature and extent of data and knowledge gaps.
2.1 Literature Search Methodology
The literature review was conducted as an iterative process by listing issues to inform an initial literature search. Can-
didate source documents were compiled, screened according to the critical questions, and then sorted according to
subject. A combination of methods was used to identify documents included in the literature review. These methods
included use of internet search engines; personal communications with experts, such as the contact people for each of
the case studies; agency internet sites, such as the web pages for individual WQT programs; reviewer comments; and
references contained in publications already identified. A complete list of all documents identified during the literature
review is composed as an annotated bibliography in Appendix A.
The following internet search engines and search terms were used to identify relevant documents.
Table 2-1. Internet Search Engines and Search Criteria
Search engines
Agricola
http://agricola.nal.usda.gov/webvoy.
htm
Ecological Society of America
http://www.esajournals.org/esaonline/
?request=search-simple
Elsevier
http://www.elsevier.com
Google Scholar
http://scholar.google.com/
Search terms
Wetland and nitrogen, wetland and treatment, wetland and con-
structed, WQT, assess WQT, assess nutrient trade, assess nutrient
credit, assess nutrient models, validate nutrient models, compare
nutrient models, nutrient trading
Wetlands, nitrogen, nutrients, WQT, nutrient trading
Minnesota Pollution Control Agency (MPCA), Rahr Malting Com-
pany (Rahr), Cherry Creek, publications, WQT, total maximum daily
loads (TMDL), equivalence, wetlands AND WQT, specific author
names, nutrient trading
WQT, NPS trading, pollutant trading programs, North Carolina case
study specific terms: Tar-Pamlico, Neuse, Trading Program, water
quality, wetlands, specific author names, TMDL, nutrient trading
Date limits
2000 to January
2006
None
None
None
-------
Search engines
Google
http://www.google.com
PubMed database
http://www.ncbi.nlm.nih.gov/entrez/
query. fcgi?CMD=search&DB=pubmed
Science Direct
http://www.sciencedirect.com/
State environmental organization
search engines
Wetlands website (SWS journal)
http://www.sws.org/wetlands/
Environmental Trading Network (ETN)
http://www.envtn.org/index.htm
Environmental Law Institute
http://www2.eli.org/index.cfm
Search terms
WQT, assess WQT, assess nutrient trade, assess nutrient credit,
assess nutrient models, validate nutrient models, compare nutrient
models, MPCA, Rahr, Cherry Creek, WQT, Idaho DEQ, Idaho Soil
Conservation Commission (ISCC), Lower Boise River (LBR), nitro-
gen, phosphorus, TMDL, equivalence, wetlands AND WQT, specific
author names, nutrient trading
Wetlands, nitrogen, nutrients, WQT, NPS trading, nutrient trading
Wetlands, nitrogen, nutrients, assess WQT, assess nutrient trade,
assess nutrient credit, assess nutrient models, validate nutrient mo-
dels, compare nutrient models, WQT, NPS trading, nutrient trading
MPCA, Rahr, Cherry Creek, publications, WQT, TMDL, equivalence,
wetlands AND WQT, specific author names, NPS pollution, nutrient
trading
Wetlands, nitrogen, nutrients, WQT nutrient trading
Workshops
2nd National Water Quality Trading Conference, held May 23-25,
2006 in Pittsburgh.
(http://www.envtn.org/WQTconf_agenda.htm)
Environmental Credits Generated Through Land-Use Changes:
Challenges and Approaches held March 8-9, 2006 in Baltimore.
http://www.envtn.org/LBcreditsworkshop/agenda.htm
Workshop
National Forum on Synergies Between Water Quality Trading and
Wetlands Mitigation Banking held July 11-12, 2005 in Washington,
DC.
http://www2.eli.org/research/wqtjTiain.htm.
Date limits
None
None
None
None
None
None
None
2.2 Literature Review Questions
Literature screening criteria are grouped into three categories: Level 1 - Preliminary Screening Questions for Identifi-
cation of Case Studies; Level 2 - Case Study Analysis Questions; and Level 3 - General "State of the Art" Questions.
The case studies are used to address the Level 1 and 2 questions. The Level 3 group of questions was created with
the recognition that the case studies may not be able to directly answer these questions.
2.2.1 Level 1 - Preliminary Screening Questions for Selection of Case Studies
1. Are there any published case studies of WQT programs within the United States or other countries?
2. How far (spatially) are the benefits of a local nutrient load reduction realized within a water body? How does
this vary for different designated water uses? How does this vary between watersheds or different water
body types (e.g., estuary, river, lake) with distinct hydrologic, geologic, and ecologic conditions? How can
appropriate geographic trading areas be established?
3. To what extent does seasonal variability need to be accounted for in trading programs?
4. What are the economic factors that drive the feasibility of various nutrient load reduction measures? How
do these factors vary depending on location and watershed conditions?
5. How should the cap for nutrient concentrations in water bodies be defined, especially in multi-state waters?
How should a baseline be established?
6. What factors determine the effectiveness of wetlands for reducing or removing nutrients from surface wa-
ter?
7. If the price for a nutrient loads reduction credit from an NPS is fixed (e.g., $/lb) within a trading program,
how are agencies determining the credit price?
-------
8. How can nutrient reductions from NPSs be quantified? How is "effectiveness" of various management
practices measured and documented? How can a reduction be measured after a management practice
has been implemented? How can the initial NPS nutrient load be quantified?
9. What are the various ways that trading is being managed? What are the advantages (or drawbacks) of
each management approach? To what extent is the management approach dependent on program scale
or types of water body included in the program?
10. For multi-state (multi-jurisdiction) trading programs, how can legal authority be established?
2.2.2 Level 2 - Case Study Analysis Questions
1. What have been the key drivers for the implementation of a WQT focused on nutrients, or other environ-
mental performance trading programs (such as air quality and wetland mitigation)?
2. What factors contribute to the success of active WQT programs or limit their effectiveness?
3. What type of institutional framework can provide accountability of NPSs? How can compliance with regula-
tions be assured and enforced?
4. What role should environmental groups have in the planning and implementation process? How much public
participation is appropriate?
5. What is public perception of water-borne stressor (nutrient) trading programs? Are there organizations op-
posed to this type of program?
2.2.3 Level 3 - General "State of the Art" Questions
1. What federal regulations and guidance documents address WQT?
2. What state regulations and guidance documents address WQT?
3. Which states have active WQT programs?
2.3 Case Study Selection
A few basic selection criteria were used to choose case studies from the list of existing WQT programs compiled in
Table 2-2. The selection criteria include type of program (PSs and NPSs); constituent traded (nitrogen and phosphorus);
implementation status (the program needed to be fully developed); whether or not wetland construction/enhancement
could be used to generate credits; geographic distribution; and the availability of published literature. Four case studies
were selected:
1. Cherry Creek, Colorado
2. Minnesota River and Rahr, Minnesota
3. LBR, Idaho
4. Tar-Pamlico River and Neuse River, North Carolina
These case studies were selected to represent programs in different regions of the country in an attempt to illustrate
region-specific issues or limitations on feasibility if they exist. To the extent possible, case studies were selected to
include distinct watershed types varying in scale, topography, land use distribution, and proximity to coastal waters.
Market structure was not a selection criteria; the Cherry Creek and North Carolina programs may not fit the definition
of a "true market" because purchase and sale of credits occur via a clearing house. In addition, water quality credits in
the North Carolina program function more like an exceedance tax than trades within a market. The need for published
literature on the WQT program was also a factor that shaped this analysis. Of the more than 80 WQT programs, pilots,
and simulations identified in the process of selecting the four case studies, these programs are among the longest-
standing. All were developed before the USERA Water Quality Trading Policy was published in 2003, although these
programs are far from static. As a result, it is likely that some of the newest programs have already been able to apply
lessons learned from the programs in their design and implementation.
The collective results of the case studies combined with the results of the literature review are used to identify common
lessons learned, successes and failures, and variations in key issues related to geography, watershed scale, land use,
and any other factors observed to affect the success of the case study trading programs.
-------
Table 2-2. Waterborne Stressor (Nutrient) Trading Programs
Project
1. Montgomery Water
Works and Sanitary
Sewer Board
2. City of Santa Rosa
3. Grassland Area Trad-
able Loads Program
4. Lake Tahoe Water Qual-
ity Trading Strategy
5. Sacramento Regional
County Sanitation
District's Mercury Offset
Program
6. San Francisco Bay Mer-
cury Offset Program
7. Bear Creek Trading
Program
8. Boulder Creek Trading
Program
9. Chatfield Reservoir
Trading Program
10. Cherry Creek Basin
Trading Program
11. Clear Creek Trading
Program
12. Lower Colorado River
13. Lake Dillon Trading
Program
Water body
Coosa River
Russian River
San Joaquin River
Lake Tahoe
Sacramento Area
San Francisco Bay
Bear Creek Res-
ervoir
Boulder Creek
Chatfield Reservoir
Cherry Creek
Reservoir
Clear Creek
Colorado River
Dillon Reservoir
State
AL
CA
CA
CA&NV
CA
CA
CO
CO
CO
CO
CO
CO
CO
Constituent
Undefined
- nutrients
Undefined
- nutrients
Selenium
Nutrients
and sedi-
ment
Mercury
Mercury
Phosphorus
Nitrogen
Phosphorus
Phosphorus
Heavy Met-
als
Selenium
Phosphorus
Ref.
(doc#)
10
10
10,261
10
10
10
10
10
10, 114
1, 10, 11,
150,225,
293
10, 181
10
10, 181,
236,149
Program-
specific
papers
No
No
Yes
No
No
No
No
No
Yes
Yes
Yes
No
Yes
Wetlands used in
trading?
No
No
No
Yes - wetland con-
trols, wetland type
not specified
No
No
No
Yes - habitat
restoration and con-
structed wetlands
(riparian)
? - BMPs for
stream bank resto-
ration and stormwa-
ter runoff
Yes - constructed
wetlands, (riparian)
No
No
No
Candidate study (why)
No-
Initial development
No-
No trading
No-
Selenium trading
No-
Initial planning stages
No-
Mercury trading
No-
Mercury trading
No-
Point-to-point
No-
Limited information avail-
able
No-
Limited information avail-
able
Yes-
One of the original projects
involved creation of a wet-
land. Credits established on
case-by-case basis.
No-
Mine discharge
No-
Selenium trading
No-
Wetlands not used
CD
-------
Table 2-2. Waterborne Stressor (Nutrient) Trading Programs
Project
14. Long Island Sound Trad-
ing Program
15. Blue Plains Wastewa-
ter Treatment Plant
(WWTP) Credit Creation
16. Tampa Bay Cooperative
Nitrogen Management
1 7. Lake Allatoona Water-
shed Phosphorus Trad-
ing Program
18. Cargill and Ajinomoto
Plants Permit Flexibility
19. Bear River Basin
20. Lower Boise River Ef u-
ent Trading Demonstra-
tion Project
21. Mid-Snake River Dem-
onstration Project &
Development of Idaho
Water Pollutant Trading
Requirements
22. Lake Erie Land Compa-
ny/Little Calumet River
23. Illinois Pretreatment
Trading Program
24. Piasa Creek Watershed
Project: Water Quality
Trading - PS for NPS
25. Monocacy River
26. St. Martin's River Water-
shed
27. Wicomico River
28. Charles River Flow Trad-
ing Program
Water body
Long Island Sound
Chesapeake Bay
Tampa Bay
Lake Allatoona
Watershed
Des Moines River
Bear River
Lower Boise River
Mid-Snake River
Little Calumet
River
IL waters
Piasa Creek Wa-
tershed
Monocacy River
St. Martin's River
Watershed
Wicomico River
Charles River
State
CT
VA
FL
GA
IA
ID, WY,
UT
ID
ID
IN
IL
IL
MD
MD
MD
MA
Constituent
Nitrogen
Nitrogen
Nitrogen
Phosphorus
Ammonia
and CBOD
Phosphorus
Phosphorus
Phosphorus
Undefined
Multiple
Sediment
Undefined
Undefined
Undefined
Water ow
Ref.
(doc#)
1, 10,
174
10
10
10, 195,
215
10
1, 10,
174, 270,
236
10
10
10, 36
10
10
10
10, 98
Program-
specific
papers
Yes
Yes
Yes
No
No
Yes
No
No
No
Yes
No
No
No
Yes
Wetlands used in
trading?
No
No
No
? - type not speci-
fied
?
Yes - Constructed
wetlands, wetland
type not specified
No
No
No
? - sed. ctrl. struc-
tures
No
No
No
Candidate study (why)
No-
Point-to-point
No-
Point-to-point
No - Wetlands not used
No-
In development
No-
Limited information available
No-
In development
Yes-
Constructed wetlands on ap-
proved BMP list, which also
identified life span.
No-
Limited information available
No-
Initial development
No-
Point-to-point
No-
No wetlands
No-
Initial development
No-
Initial development
No-
Initial development
No-
Water ow trading
-------
Table 2-2. Waterborne Stressor (Nutrient) Trading Programs
Project
29. Edgartown WWTP
30. Falmouth WWTP
31. Massachusetts Estuar-
ies Project
32. Nashua River
33. Town of Acton POTW
34. Specialty Minerals, Inc.
in Town of Adams
35. Wayland Business
Center Treatment Plant
Permit
36. Maryland WQT Policy
37. Kalamazoo River Water
Quality Trading Demon-
stration
38. Michigan Water Quality
Trading Rule Develop-
ment
39. Saginaw River Basin
40. Minnesota River Basin
41. Minnesota River WQT
Study
42. Rahr Permit (lower Min-
nesota River)
Water body
Edgartown River
Falmouth Harbor
Popponesset Bay,
Three Bays and
Warham Bay and
Agawam River
Nashua River
Assabet River
Hoosic River
Sudbury River
Chesapeake Bay,
other MD waters
Kalamazoo River,
Lake Allegan
Ml waters
Saginaw River
Basin
Minnesota River
Minnesota River
Minnesota River
State
MA
MA
MA
MA
MA
MA
MA
MD
Ml
Ml
Ml
MN
MN
MN
Constituent
Nitrogen
Nitrogen
Nitrogen
Phosphorus
Phosphorus
Temperature
Phosphorus
Phosphorus
and nitrogen
Phosphorus
Phosphorus
and nitrogen
Nutrients
and sedi-
ment
Phosphorus
Phosphorus
Phosphorus,
nitrogen,
CBOD5 and
sediment
Ref.
(doc#)
10
10
10
10
10
10
10
10
10,261,
233, 236,
204, 226
1, 10,
174,236
236
10,63,
174,233,
236,105,
242, 252
10
1, 10,
261, 133,
193, 194
Program-
specific
papers
No
No
No
No
No
No
No
Yes
Yes
Yes
Yes
Yes
Yes
Yes
Wetlands used in
trading?
No
No
Yes - wetland type
not specified
No
No
No
No
No
agri. BMPs
No
? - type not speci-
fied
Yes - BMP and
wetland type not
specified
No
Yes - restored
riparian wetlands
Candidate study (why)
No-
Sewer/septic only
No-
Sewer/septic only
No-
Limited information available
No-
Initial development
No-
No trades
No-
Temperature trading
No-
Sewer/septic only
No-
Wetlands not used
No-
Wetlands not used
No-
Regs. only
No-
No trades
Yes-
High volume of trades
No-
Point-to-point
Yes-
Specifically tied to National
Pollutant Discharge Elimina-
tion System (NPDES) permit
requirements
-------
Table 2-2. Waterborne Stressor (Nutrient) Trading Programs
Project
43. Southern Minnesota
Beet Sugar Cooperative
Plant Permit
44. Mississippi River/Gulf of
Mexico
45. Chesapeake Bay WQT
Program
46. Great Lakes Trading
Network
47. Cape Fear River Basin
48. Neuse River Nutrient
Sensitive Water (NSW)
Management Strategy
49. Tar-Pamlico Nutrient Re-
duction Trading Program
50. Passaic Valley Sewer-
age Commission Ef u-
ent Trading Program
Water body
Minnesota River
Mississippi River/
Gulf of Mexico
Chesapeake Bay
Great Lakes
Cape Fear River
Neuse River Estu-
ary
Pamlico River
Estuary
Hudson River
State
MN
MS
Multiple
states
multi-de-
fined by
individ-
ual pro-
grams
NC
NC
NC
NJ
Constituent
Phosphorus
Phosphorus
and nitrogen
Phosphorus
and nitrogen
Undefined
Undefined
Nitrogen
Phosphorus
and nitrogen
Heavy Met-
als
Ref.
(doc#)
1, 10
233, 68,
30, 31,
74, 76
10
10
10, 174,
96,46,
129, 132,
46, 129,
132
1, 10,
261, 178,
96, 157,
236, 52,
112, 116,
128, 130,
131, 151,
178
10
Program-
specific
papers
Yes
Yes
Yes
Yes
Yes
Yes
No
Wetlands used in
trading?
Yes - constructed
wetlands, wetland
type not specified
Yes - wetland resto-
ration, wetland type
not specified
No
No
Yes - wetland
restoration and con-
structed wetland,
wetland type not
specified
Yes - wetland
restoration and
constructed wetland
(riparian)
Yes - emphasis on
agricultural BMPs,
wetland restoration
and constructed
wetland (riparian)
No
Candidate study (why)
No-
Limited information available
Yes-
But in concept stage of devel-
opment
No-
Wetlands not used
No-
See Kalamazoo
No-
Initial planning stages
Yes-
Cooperative - PS purchase
credits, central agency (North
Carolina Wetland Restoration
Fund) allocates funds to proj-
ects. Nutrient offset payments
targeted toward restoration of
wetlands and riparian areas
within the Neuse River Basin.
Yes-
One of the oldest trading
programs in the US. Coop-
erative - PS purchase credits,
central agency allocates funds
to projects.
No-
Dissolved metal trading
-------
Table 2-2. Waterborne Stressor (Nutrient) Trading Programs
Project
51. Truckee River Water
Rights and Offset Pro-
gram
52. East River
53. New York City Water-
shed Phosphorus Offset
Pilot Programs
54. Greater Miami River
Watershed Trading Pilot
Program
55. Clermont County Project
56. Ohio River Basin Trad-
ing
57. Shepard Creek (tribu-
tary to Mill Creek)
58. Honey Creek Watershed
59. Lower North Canadian
River
60. Tualatin River Water-
shed NPDES Permits
61. Conestoga River
62. Pennsylvania Water-
based Trading Simula-
tions
63. Pennsylvania Multimedia
Training Registry
Water body
Truckee River
East River
Hudson River
Greater Miami
River Watershed
Little Miami River,
Harsha Reservoir
Ohio River Basin
Shepard Creek
Honey Creek
Lower North Cana-
dian River
Tualatin River
Watershed
Conestoga River
Delaware River,
Moshanon Creek,
Swatara Creek
and Spring Creek
State-wide
State
NV
NY
NY
OH
OH
OH
- Multi-
state
OH
OH
OK
OR
PA
PA
PA
Constituent
Phosphorus,
nitrogen,
or total
dissolved
solids
Nitrogen
Phosphorus
Phosphorus
and nitrogen
Phosphorus,
nitrogen
or total
dissolved
solids
Nutrients
Peak storm-
water ows
Phosphorus
Undefined
Temperature
Phosphorus
and nitrogen
Multiple
Phosphorus
and nitrogen
Ref.
(doc#)
10
10, 166
10
10
10
10
256
10
10
10
10
10
10
Program-
specific
papers
No
No
Yes
Yes
No
No
Yes
No
No
No
No
No
No
Wetlands used in
trading?
No
No
Yes - wetland
restoration, type not
specified
? - see types of
agricultural BMPs
No
No
No
No
No
No
No
No
No
Candidate study (why)
No-
Wetlands not used
No-
Point-to-point
No-
Limited information available
No-
Limited information available
No-
Wetlands not used
No-
Initial development
No-
Stormwater retention
No-
BMP case study, not trading
No-
Feasibility study
No-
Riparian restoration
No-
Wetlands not used
No-
Simulation, not program
No-
Wetlands not used
-------
Table 2-2. Waterborne Stressor (Nutrient) Trading Programs
Project
64. Ef uent Trading Pro-
gram
65. Boone Reservoir
66. Colonial Soil and Water
Conservation District
67. Henry County Public
Service Authority and
City of Martinsville
Agreement
68. Virginia Water Quality
Improvement Act and
Tributary Strategy
69. Chehalis River
70. Puyallup River
71. Yakima River
72. Fox-Wolf Basin Wa-
tershed Pilot Trading
Program
73. Red Cedar River Pilot
Trading Program
74. Rock River Basin Pilot
Trading Program
75. Wisconsin Ef uent Trad-
ing Rule Development
76. West Virginia Trading
Framework
Water body
Providence and
Seekonk Rivers,
Rhode Island
Boone Reservoir
Lower James River
Smith River
Chesapeake Bay,
other VA waters
Chehalis River
Puyallup River
Yakima River
Green Bay
Ta inter Lake
Rock River Basin
Wl waters
State-wide
State
Rl
Total
nitrogen
(TN)
VA
VA
VA
WA
WA
WA
Wl
Wl
Wl
Wl
WV
Constituent
Salinity
Phosphorus,
nitrogen and
BOD
Nutrients
and sedi-
ment
Total dis-
solved
solids
Phosphorus
and nitrogen
Undefined
Ammonia
and BOD
Water ow
Phosphorus
Phosphorus
Phosphorus
Phosphorus
Multiple
Ref.
(doc#)
10
10
10
10
10
10
10
10
10, 178
10
10,236
10
10
Program-
specific
papers
No
No
No
No
No
No
No
No
Yes
Yes
Yes
No
No
Wetlands used in
trading?
No
No
No
No
No
No
No
No
No
No
Yes - wetland resto-
ration (return farm-
land to wetland),
type of wetland not
specified
No
? - some info on
wetlands, type not
specified
Candidate study (why)
No-
Salt trading
No-
No program developed
No-
Planning
No-
Point-to-point
No-
Planning
No-
Not implemented
No-
No trades
No-
Water quantity
No-
Point-to-point, nonpoint not
defined
No-
Wetlands not used
No-
Limited information available
No-
Wetlands not used
No-
Concept stage
-------
Table 2-2. Waterborne Stressor (Nutrient) Trading Programs
Project
77. Cacapon/Lost River
78. Cheat River, West Vir-
ginia
79. Hunter River Salinity
Trading, USEPA Depart-
ment of Environment
and Conservation
80. Dutch Nutrient Quota
System
81. South Nation River
Watershed
82. Kaoping River Basin
Water body
Lost River
Cheat River
Hunter River
Country-wide
South Nation River
Kaoping River
Basin, Taiwan
State
wv
wv
Australia
Nether-
lands
Ontario,
Canada
Taiwan
Constituent
Undefined
Heavy
Metals and
acidity
Salinity
Nutrients
Phosphorus
Multiple
Ref.
(doc#)
10
10
34, 273,
272, 290
70, 75
Program-
specific
papers
No
No
Yes
Yes
Yes
No
Wetlands used in
trading?
No
No
No
No
?
No
Candidate study (why)
No-
Feasibility study
No-
Concept stage
No-
Salinity trading
No-
Livestock production
No-
Focus on agriculture BMPs
and riparian stabilization
No-
Limited information available
Candidates for case studies are highlighted in green.
CBOD = carbonaceous biological oxygen demand.
-------
3.0 Literature Review-Wetland Nutrient Removal
The utility of wetlands in managing nutrient loads and their historical, current, and anticipated future implications in
WQT warrant focused review. Numerous studies or summaries of studies have investigated the function of wetlands
in the removal of pollutants, including high levels of nutrients (USEPA, 2005a; Fisher and Acreman, 2004; Mitsch and
Gosselink, 2000; Hunt and Poach, 2001; Kadlec and Knight, 1996; USEPA, 1999; USEPA, 1993a; Cooper and Findlater,
1990). Results from these studies have been summarized and used to guide the development of constructed wetlands
to treat water high in nitrogen and phosphorus (Kadlec and Knight, 1996). This review does not attempt to re-summarize
these studies, but references them for readers who desire more information. Rather, this review summarized information
on the nutrient removal function of wetlands specifically applicable to WQT.
A bibliography of published documents regarding constructed wetlands was compiled by USDA staff from the Ecological
Sciences Division of the Natural Resources Conservation Service (NRCS) and the Water Quality Information Center at
the National Agricultural Library. The references were acquired in part through searches of the AGRICOLA database.
The bibliography has been updated several times, most recently in June of 2000, and contains hundreds of entries,
many with abstracts (USDA, 2000). An annotated bibliography of urban stormwater and nonpoint nutrient control was
conducted by the Washington State Department of Ecology in 1986 and updated in 1991. The review was conducted
to determine the extent of information available on the long-term ecological impacts of stormwater on wetlands and on
the ability of wetlands to improve the water quality of urban stormwater (Stockdale, 1991).
Both constructed and natural wetlands function to buffer downstream nutrients by storing and transforming nutrients,
which are gradually released downstream (DeBusk, 1999). Consequently, wetlands have been considered an effective
means to treat PSs and NPSs of nutrients and improve water quality in downstream lakes and rivers. The benefits of
using wetlands to treat NPSs of pollutants include the ability to operate under a wide range of hydraulic loads, provide
internal water storage capacities, and remove or transform contaminants (Dierberg et al., 2002).
3.1 Wetland Removal of Nitrogen and Phosphorus - Technical Overview
Nutrients enter wetlands through various geologic, biologic, and hydrologic pathways; however, hydrologic inputs gener-
ally dominate elemental inputs into wetlands. The cycling of nutrients in wetlands has been extensively described and
studied (Mitsch and Gosselink, 2000). Inundation, water level uctuations, and biota result in both aerobic and anaerobic
processes within the water column and wetland soils. These processes allow the transformation of nutrients like nitrogen
and phosphorus as they interact with the biogeochemistry of the wetland environment.
Wetlands function to remove phosphorus through sedimentation, plant uptake, organic matter accumulation, immobiliza-
tion, and soil sorption. Nitrogen is removed in wetlands by filtration, sedimentation, uptake by plants and microorganisms,
adsorption, nitrification, denitrification, and volatilization. Gaseous losses of nitrogen through denitrification are generally
the most significant nitrogen removal mechanism in natural as well as constructed freshwater wetlands (DeBusk, 1999;
Bowden, 1987; Faulkner and Richardson, 1989).
A description of inputs, outputs, and internal cycling of nutrients in wetlands can be described by chemical mass balances.
These mass balances for wetlands have been developed and discussed by others to describe the functions of wetlands
in nutrient production and cycling. Literature reviews of this subject have been provided by DeBusk (1999), Nixon and
Lee (1986), Johnston et al. (1990), and Johnston (1991). However, few investigators have developed a complete mass
balance for wetlands that includes measurement of all the nutrient pathways, sources, and sinks. Despite this lack of
comprehensive study, some generalizations have been made (Mitsch and Gosselink, 2000).
The function of wetlands as sources, sinks, and transformers of nutrients depends on the wetland type, hydrologic
condition, and the length of time the wetland is subjected to nutrient loading. Wetlands have been shown to be sinks
or storage places for nitrogen and phosphorus, although not all wetlands exhibit this trait. One study found seasonal
and permanent swamps had a net export of organic matter. Most of the inorganic phosphorus (60 to 90 percent) was
retained, but there was a net release of nitrates, probably associated with the net export of organic matter (Mwanuzi et
al., 2003). The location and chemical form of nutrients change within wetlands during the exchange of water and sedi-
ment as well as during plant uptake and decomposition (Atlas and Bartha, 1981). The availability of nutrients and the
13
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extent to which biogeochemical processes function affect the intracycling of nutrients and the productivity in wetlands.
The function of wetlands is closely related to adjoining land and water bodies; changes upgradient of a wetland will
affect processes occurring within the wetland. For example, the depth of an adjoining water body or the conveyance
capacity of the outlet stream are likely to modulate functions such as depth and storage capacity of natural wetlands
(Kadlec and Knight, 1996).
The productivity of wetlands is also directly correlated with nutrient input and transformation. Thus, the ability of wetlands
to store and transform nutrients is directly connected to the amount of nutrients available for storage and transformation.
However, this ability is not limitless, and once storage and transformation capacity is reached, excess nutrients leave
the wetland through atmospheric, surface, and subsurface out ows (Mitsch and Gosselink, 2000). If long-term nutrient
removal is an objective of a constructed wetland, significant maintenance up to and including re-construction may be
necessary, although expecting a constructed wetland to perform this function in perpetuity is likely ecologically and
economically unrealistic at best, and not reasonably feasible at worst.
Although several generalizations can be made regarding the function of wetlands as sources, sinks, and transformers
of nutrients, the complex and unique situation revolving around each wetland limits the application of generalizations.
Wetlands can be a sink for a form of nitrogen at one moment in time and a source for the same nitrogen element at
another time. Generalizations are also hampered by inconsistent study results and by the variety and imprecision of
approaches to measuring nutrient uxes in wetlands. There is little consensus in the literature about nitrogen and phos-
phorus fate in wetlands. A few chemical imbalances have been studied and described, but a complete mass balance for
wetlands has yet to be developed (Mitsch and Gosselink, 2000). Furthermore, there has been a terrestrial-biased (i.e.,
applying processes found in uplands) approach in wetland research, especially regarding vegetation and productivity,
that limits the understanding and employment of soil and microbial processes specific to wetlands in nutrient reduction
(Wetzel, 2001; Johnston, 1991).
The chemical transformation of nitrogen and phosphorus is important to understanding how wetlands perform in nutri-
ent removal and sequestration. Inorganic and organic nitrogen and phosphorus enter wetlands through water inputs
such as overland runoff, outfall pipes, groundwater, and to a lesser degree rainfall. The inorganic and organic forms
are transformed or stored in the water, soil, and biota through several processes, including nitrification, denitrification,
ammonification, diffusion, plant uptake, litterfall, decomposition, adsorption, precipitation, sedimentation, volatilization,
and peat accretion (DeBusk, 1999). Following transformation and storage, both inorganic and organic forms of nitrogen
and phosphorus exit the wetland in water out ows or by gaseous states such as nitrogen gas (N2). Other gases are
emitted from wetlands, including carbon dioxide (CO2), nitrous oxide (N2O), and methane (CH4), which are produced
under highly reduced conditions (Mitsch and Gosselink, 2000).
To use wetlands to reduce nutrients from water before the ows enter downstream water bodies, the amount of nutrients
in the wetland out ow needs to be less than in the wetland in ow, and the reduction must be measurable. The USEPA
found that sequential nitrogen transformation within wetlands used to treat water quality results in a unidirectional shift
of elevated total and organic nitrogen forms to oxidized or gaseous nitrogen forms (USEPA, 1999). In addition, plant
detritus provides long-term storage of nitrogen in wetlands, and a portion of this nitrogen can eventually become avail-
able for nutrient cycling following decomposition, which can take from months to many years (Kadlec and Knight, 1996).
A summary of data collected in North American Wetlands for Water Quality Data Base (NADB) found that free water
surface wetlands on an annual mean average removed 61 percent of the total phosphorus (TP) in in ow water with a
standard deviation (SD) of 30 percent (USEPA, 1999). An approach to control the impacts of elevated nutrients is for
the nutrients to be in a form not readily available to biotic organisms such as algae, which consume oxygen during
uptake of nutrients. For example, phosphorus chemically bound to minerals (e.g., iron, aluminum, calcium, and organic
compounds) is not as readily available as dissolved phosphorus to algae or plants, but represents a long-term source
of phosphorus in a water system (NRCS, 2001).
One of the key environmental drivers in nutrient transformation is inundation. Inundation affects the oxygen content of
the soil and produces anaerobic conditions, although the near-surface soil tends to retain an oxidized layer due to the
proximity to the water column, oxygen translocation within rooted plants, and microbial activity (Tanner, 2001 a). Some
studies have found oxygen availability to the sediment was the greatest limiting factor for nitrification (White and Reddy,
2003). Oxidation affects the reduction of elements such as iron, resulting in a brownish-red color at the soil surface
compared to the bluish-gray color of reduced sediments dominated by ferrous iron. Subsurface systems have been
found to display marginal or negative nitrogen removal because of the lack of oxygen (USEPA, 1993a). Inundation also
affects pH and redox potential, which in uences the rates of nutrient transformation (Mitsch and Gosselink, 2000).
The results from studies on nutrient removal have shown inconsistencies in amount and efficiency of nutrient removal.
For example, results from an experimental constructed wetland showed that nutrient removal was primarily the result
of plant uptake and harvesting (15 percent of TN input, 10 percent ofTP input). Other processes had a relatively minor
contribution: denitrification (8 percent of TN input), sedimentation and accumulation of organic matter in the soil (7 per-
cent of TN input, 14 percent of TP input) (Meuleman et a/., 2003). Other studies have shown that denitrification is one
14
-------
of the more important mechanisms for removing nitrogen in wetlands. Nitrogen removal from septage with high solids
concentration resulted from sedimentation of waste solids (57.6 percent), denitrification (40.9 percent), and direct uptake
by plants (0.5 percent) of the total in uent nitrogen (Hamersley et a/., 2001). Recent studies show a wide range of nutrient
removal efficiency values. Studies of constructed surface ow wetlands in Norway found nitrogen removal efficiencies
between 3 and 15 percent, due to high hydraulic load and low temperatures (Braskerud, 2002). In constructed horizontal
reed bed wetlands in Germany, more than 90 percent removal of TN and phosphorus was achieved (Luederitz et a/.,
2001). A compilation of data from 60 studies of 57 natural wetlands in 16 countries showed the mean percent change
in nutrient load between water entering and exiting the wetlands was 67 percent (SD of 27 percent) for nitrogen and
58 percent (SD of 23 percent) for phosphorus (Fisher and Acreman, 2004).
One of the primary ways nutrients are removed from in ow waters is through storage within the wetlands, typically
within soil, organic matter, or biota. For example, phosphorus is stored in wetlands in the soil by adsorption (i.e., surface
accumulation) with sediment particles and precipitation with other compounds, within peat and plant litterfall, and in
living plant and animal biomass (e.g., bacteria, algae, and vascular macrophytes). Sediment containing high organic
matter accumulated twice the nitrogen (Tanner, 2001 b) and six times the phosphorus (Tanner, et a/., 1998) of live and
dead plant tissue. Peat is considered a long-term storage location for nutrients (DeBusk, 1999). One study found that
twice as much phosphorus was sequestered in submerged aquatic vegetation as in sediment, but these nutrients had a
greater probability to be mobilized as plants decay (Dierberg et a/., 2002). Dissolved organic phosphorus and insoluble
forms of organic and inorganic phosphorus are generally not biologically available until they are transformed into soluble
inorganics (Mitsch and Gosselink, 2000). Therefore, both storage of phosphorus within wetlands and the reduction of
downstream export of soluble inorganic phosphorus decrease the effective nutrient load of downstream waters and the
associated eutrophication.
Nutrient removal in constructed wetlands has been found to follow a seasonal pattern in most temperate conditions.
The amount of nitrogen and phosphorus removed depends on the form of the nutrient, type and density of the aquatic
plants, nutrient loading rate, and climate. During winter, nutrients sequestered in plants and plankton are released back
into the water column upon decomposition (USERA, 1999). Typically, nutrients taken up by plants and microorganisms
in dissolved organic forms are returned later in complex organic forms (Tanner, 2001 a). Seasonal temperatures also
in uence transformation of nutrients. For example, nitrification is limited by temperature during all seasons when plant
gas exchange and oxygen input into the rhizosphere are limited. Denitrification was almost complete in midsummer
and was restricted at seasonal temperatures below 15°C in a study conducted on a constructed subsurface horizontal
ow wetland in Germany (Kuschk et a/., 2003). Spring and autumn removal efficiencies responded to the nitrogen load
in a linear fashion. Efficiencies in winter and summer differed extremely (mean removal rates of 0.15/0.7 g m 2 d 1
[11 percent/53 percent] in January/August) and appear to be independent of the nitrogen load (0.7-1.7 gm 2d 1)
(Kuschk et a/., 2003). Wetland treatment systems in Hungary showed that removal performances varied by 40 percent
between summer and winter (Szabo et a/., 2001). Several studies found that temperate regions show a rapid uptake of
nutrients in early spring with rising temperatures, which stimulates mineralization of organic matter accumulated over
the previous winter (Tanner, 2001 a).
Although several studies demonstrated seasonal in uences in water quality performance, a study of constructed wet-
lands in Florida found no seasonal pattern in phosphorus removal despite uctuations in air temperature and sunshine
(Dierberg et a/., 2002). Sub-tropical wetlands lack the annual cycle of fall-winter senescence and nutrient release that
is characteristic of northern climates. However, this lack of seasonality may add to the long-term stability of sediments
and detritus-bound nutrients in sub-tropical regions. Another regional characteristic found in Florida, but applicable to
other similar areas, is the high level of calcium and high alkalinity in runoff. This regional condition of runoff allowed
more phosphorus to be sequestered by co-precipitation with calcium carbonate (Dierberg et a/., 2002). These examples
illustrate the in uence regional factors have on nutrient removal performance of wetlands and may explain why wetland
nutrient removal performance is better in some regions than in others.
Climate in uences the amount and timing of nutrient input, as well as nutrient concentration and transformation within
wetlands (Mitsch and Gosselink, 2000). Temperature affects growth and productivity of wetland biota. Also, oxygen lev-
els in wetlands uctuate with temperatures; oxygen saturation is greater at cooler temperatures. Oxygen levels, in turn,
affect several nutrient transformation processes. For example, Woodwell and Whitney (1977) found a salt marsh uptake
of phosphate in cold months and export of phosphate in warm months. Areas with high precipitation have increased
hydrologic inputs, which can dilute nutrient concentration or increase nutrient concentrations if the precipitation picks
up nitrogen and phosphorus before entering the wetland through overland or groundwater ows. A study of several
streams throughout the United States found that concentrations of nitrogen and phosphorus increased with precipitation
in disturbed watersheds because of increased erosion, but decreased with stream ow in natural watersheds, presum-
ably because of reduced erosion and increased dilution (Omernik, 1977). Arid regions can concentrate nutrients as
water evaporates from wetlands, which leaves increased salts, affecting chemical binding rates and biological diversity.
Additionally, groundwater may be more in uential in arid regions as the subsurface water picks up nutrients within the
soil prior to outfalling to wetlands (USERA, 1993a).
15
-------
Climate also has considerable effect on the plant and microorganisms growing in wetlands. The quantity and variety of
these organisms in uence the nutrient transformation and removal within wetlands. For example, temperate wetlands
retain more nutrients in the growing season primarily because of the higher microbial and macrophyte productivity.
Nutrients stored in biomass can be released back into the water column in the autumn following litter fall and subse-
quent leaching. This seasonality has application to the concept of using wetlands to reduce downstream nutrient loads.
Wetlands can function as sinks for nitrogen and phosphorus in summer, when the biotic community is most productive,
which corresponds favorably with the need to reduce summer algae blooms in downstream waters as a result of elevated
nutrients (Klopatek, 1978; Lee et a/., 1975).
Nutrient removal has been shown to be higher in wetlands containing plants, mostly through denitrification and sec-
ondarily through plant uptake (Stein et a/., 2003; Lin et a/., 2002; Jing et a/., 2002; Tanner, 2001 a). Macrophytes have
been found to enhance nutrient removal by assisting solid sedimentation, reducing algae production, improving nutrient
uptake, and releasing oxygen (Jing et a/., 2002; Bavoref a/., 2001). Studies of surface ow horizontal reed beds in Aus-
tralia found removal efficiency with plants to be greater than 96 percent for both nitrogen (9.7 milligrams per liter [mg/L])
and phosphorus (0.56 mg/L) and without plants to be 16 percent for nitrogen (1.6 mg/L) and 45 percent for phosphorus
(0.26 mg/L) (Huett et a/., 2005). Another study of constructed wetlands in Taiwan found that planted wetlands removed
80 to 100 percent of ammonium (NH4)-nitrogen (NH4-N) (Jing et a/., 2002). High denitrification rates in the presence
of plants has been attributed to a high degree of soil oxidation (Matheson et a/., 2002). An assessment of subsurface
constructed wetlands found that oxygen transport down to the roots by emergent plants was the prime source of oxygen
needed for nitrification (USERA, 1993a).
Submerged aquatic vegetation communities have been found to exhibit phosphorus removal mechanisms not found
in wetlands dominated by emergent macrophytes (Dierberg et a/., 2002). Constructed wetlands using oating aquatic
macrophytes have been used to improve drinking water supplies in Brazil (Elias et a/., 2001). The submerged plants
directly assimilated phosphorus from the water column and mediated the pH so phosphorus co-precipitated with calcium
carbonate in soil sediment. Leaves and stems can also act as nucleating sites for co-precipitation. Under high iron and
oxygen conditions, phosphorus has been found to co-precipitate on iron oxide as evident from purple plaques observed
on roots and stems, contributing to a removal efficiency of 83.6 percent (Jardinier et a/., 2001). Removal efficiencies
for organics, NH4-N, and orthophosphates were in uenced by the health and growth rate of macrophytes (Jing et a/.,
2002).
Even wetlands designed to treat wastewater through subsurface ows showed enhanced nitrogen and initial phospho-
rus removal when planted versus unplanted wetlands with gravel-bed substrates (Tanner, 2001 a). Uptake and storage
of nitrogen and phosphorus in live plant biomass accounted for a fraction (3 to 19 percent TN; 3 to 60 percent TP) of
the improved performance of planted wetlands. The author suggests that plants primarily facilitate improved nutrient
removal indirectly through their effects on other removal processes rather than direct nutrient uptake (Tanner, 2001a).
A recent study of nitrogen uptake in the rhizosphere concluded that nitrate (NO3) uptake by wetland plants may be far
more important than previously thought. The modeled calculations showed that substantial quantities of NO can be
produced in the rhizosphere of wetland plants through nitrification and taken up by the roots under field conditions and
that rates of NO3 uptake can be comparable to those of NH+4. In addition, the model showed that rates of denitrification
and subsequent loss of nitrogen from the soil remain small even where NO3 production and uptake are considerable
(Kirk and Kronzucker, 2005).
Many studies have shown that different species of plants perform better than others at nutrient removal from waste
water. Cattails were most efficient at nitrogen removal, and aquatic plants increased phosphorus removal in wetlands
constructed to treat saline wastewater in Thailand (Klomjek and Nitisoravut, 2005). Careful consideration should be given
to the choice of plant species used for nutrient removal systems. While many species can be desirable and effective for
nutrient removal in some regions, those same plants can be undesirable in other regions (Mitsch and Gosselink, 2000)
and can often be highly invasive, spreading to and causing problems in nearby aquatic systems. Other species that have
shown high rates of nitrogen removal from waste water include Phragmites (Mayo and Bigambo, 2005), Typha angus-
tifolia (Belmont et a/., 2004), Scirpus validus (Fraser et a/., 2004), and Schoenoplectus (Poach et a/., 2003). However,
some studies found that plant species had little impact on nutrient concentration or removal (Jing et a/., 2002; Huang
et a/., 2000). A study of constructed wetlands in the Florida Everglades found that species differed in their uptake and
accumulation in plant tissue, but it was a minor contributing factor in overall nutrient removal (Dierberg et a/., 2002).
In addition to plants affecting transformation processes, plants also take up nutrients into their tissues. Much of the
storage of nutrients in plants occurs in below-ground tissues, particularly in emergent species where up to 90 percent
of the plant productivity occurs in below-ground tissues (Tanner, 2001a; Wetzel, 2001). This is particularly true when
plants enter maturity and senesce as nutrients are translocated to root tissues for storage until the next growing sea-
son. Consequently, the removal of above-ground tissue is often not a practical method for removing nutrients from the
wetland (Wetzel, 2001; Matheson et al., 2002). Plant tissue analysis has shown that a single annual harvest of plant
material accounted for 10 percent or less of the nitrogen removed from constructed subsurface wetlands. Increased
harvest frequency may increase this performance, but would increase the operation costs of the constructed wetland
(USEPA, 1993a).
16
-------
Studies of the effect of hydrologic and hydraulic conditions show inconsistent results. Hydrologic and hydraulic conditions
in a wetland can in uence the efficiency of processes that remove nutrients from water (Jing et al., 2002; Sakadevan
and Bavor, 1999). Hydraulic residence time was negatively correlated with TN and phosphorus removal in constructed
subsurface ow wetlands (Schulzef a/., 2003). NH+4 and total Kjehldahl nitrogen (TKN) concentrations within a wetland
decreased exponentially with increased residence time (Huang et a/., 2000). TKN is the organically bound nitrogen in
a water sample that is released from organic matter through a digestive process before analysis. Knight et al. (2000)
found that removal of nutrients was a function of inlet concentrations and hydraulic loading rates, but in other studies
nutrient removal efficiencies were unaffected by variation in hydraulic loading rates (Lin et al., 2002). Dierberg et al.
(2002) found the greater the residence time, the greater reduction in nutrients.
Ideally, the optimal performance of a constructed wetland can be achieved by affecting the in ow concentration and
residence time. Consideration should be given to designs of constructed wetlands with localized in ows, which generate
a nutrient soil gradient. A study of wetlands used for 40 years to treat wastewater in Florida found that TP in wetlands
sediments was significantly correlated with depth and distance from the point of surface water in ow (White and Reddy,
2003). Nutrient retention has been found to be affected by wetland size relative to the watershed (and therefore reten-
tion time), land use of the watershed, any intrusion of groundwater, and the nature of the wetland in terms of its shape
and vegetation (Raisin and Mitchell, 1995). An assessment of subsurface constructed wetlands found that the media
(e.g., gravel, sand) affected the hydraulic conductivity and, subsequently, the nutrient removal performance. Systems
with sandy substrate had low conductivity and, therefore, needed to be larger in size to generate a retention capacity
effective at removing nutrients, which requires more land surface for construction and operation (USEPA, 1993a).
3.2 Factors that Affect Nutrient Load Reduction Efficiencies
Wetlands that are undersized compared to the amount of water that will ow through them are more susceptible to
frequent ushing by storms (which can ush out nutrients and organic matter) and are therefore not as effective as
properly sized wetlands. Wetlands need to be large enough to be able to store the total from the "first ush," the first
1 inch of precipitation (Hunt and Doll, 2000). Bass (2000) indicated that current recommendations are that a wetland
surface area should be at least 1 percent of the contributing watershed area. However, given that the amount of runoff
from a drainage area will vary considerably depending of the amount of impervious area within the watershed, Hunt and
Doll (2000) calculated surface areas of wetland ranging from 7 percent for a watershed with a low permeability (curve
number [CN]=98)2 to slightly more than 1 percent for residential areas with fairly clayey soils (CN=60).
This illustrates one limitation of constructed stormwater wetlands relative to other stormwater BMPs: they require a large
area of land. Wetland designs can improve the overall performance of the wetland and partially address the problem of
stormwater ows ushing wetlands by including a high ow bypass ( ow splitter) that allows larger storms to circumvent
the wetland (Hunt and Doll, 2000). In North Carolina, constructed stormwater wetlands have been located on watersheds
as small as 4 to 5 acres, but they are most commonly used for larger drainage areas and typically serve watersheds
ranging from 15 acres to more than 100 acres.
Geographic position and land use affect the nutrients owing into wetlands (Mitsch and Gosselink, 2000). The size of
the watershed, the steepness or slope of the landscape, soil texture, and variety of topography in uence these nutrient
inputs. The position of the wetland within the landscape, in addition to the climatic situation, in uence the cycling of
nutrients within and through wetlands. For example, tidal salt marshes have significant tidal exchange while closed om-
brotrophic bogs have little material exchange except for gaseous matter into and out of the wetland. Upstream wetlands
have the ability to affect the amount and form of nutrients owing into wetlands (e.g., a series of wetlands will produce
a different outcome compared to a single wetland). Land uses can affect nutrient inputs by affecting erosion rates, ap-
plying fertilizers, modifying hydrologic ows, and altering buffer features of wetlands. Adjacent land use practices also
may impact a wetland's ability to store nutrients, thereby altering the structure and function of the wetland (Gathumbi et
al., 2005). Obvious direct input from sewage ef uent, urban runoff, and industry can have dramatic impacts on nutrient
loads within wetlands. Studies of a natural wetland in New Zealand that received sewage oxidation pond ef uent for
more than 30 years showed elevated nutrient concentrations in ground and surface water, increased weed invasion and
plant growth, and high concentrations of certain heavy metals (Chague-Goff et al., 1999).
Anthropogenic sources of nitrogen and/or phosphorus include sewage, fertilizers, animal waste, erosion, industrial
discharge, mining, drinking water treatment, synthetic materials, and fossil fuel burning. As previously discussed, both
phosphorus and nitrogen are present in wetlands in inorganic and organic forms. Both nutrients are used by living or-
ganisms for basic life processes, but too much can be harmful to aquatic environments. The potentially harmful effects
associated with anthropogenic enrichment of nutrients are most noticeable in environments where these nutrients are
normally in limited supply, such as within surface water bodies (e.g., eutrophication). Nitrogen and phosphorus are often
found in higher than natural levels in areas of human activity. Consequently, the negative effects of too much nitrogen
CN reflects the ability of a watershed to store water through initial storage and subsequent infiltration. A high CN indicates a
watershed with limited storage capacity.
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and phosphorus are concentrated downstream of these areas, leading to the need to reduce nitrogen and phosphorus
within water bodies. Removal of nutrients from water before the water is discharged downstream can reduce the poten-
tial for eutrophication; however, upgrades to treatment processes cannot eliminate this potential. For example, sewage
treatment typically decreases ammonia discharge, which results in increased NO3 discharge, but does not address TN
discharge concentrations (Murphy, 2005).
Additional studies focusing on the design issues of constructed wetlands are necessary. These studies should look at
the impacts of scale and edge effects in research wetlands. Also, the delivery of treatment water at a single point or
dispersed delivery and in batches versus continuous ows should be studied further for modeling and application of
constructed wetlands and as treatment BMPs. Longer-term studies are also lacking within the literature. Further study
is needed on quantifying and comparing the oxygen release characteristics of different emergent species in response
to root-zone treatments and the effect of this release on removal efficiencies (Tanner, 2001 a).
3.3 Natural versus Constructed Wetlands
Natural wetlands exist where water inundates land, even seasonally, orgroundwater is shallow enough to create hydric
soils near the surface, which supports hydrophytic plants adapted to living in water or saturated soils. Constructed wet-
lands developed to improve water quality are defined as engineered or constructed wetlands that use natural processes
involving wetland vegetation, soils, and their associated microbial assemblages to assist in the treating of ef uent or
other water sources (USEPA, 2000a). Because constructed wetlands are typically designed specifically for water quality
improvement functions, many of the wildlife habitat functions provided by natural wetlands are lacking in constructed
wetlands (DeLaney, 1995). A third type of wetland, often referred to as a created wetlands, are often designed to pro-
vide wildlife habitat functions similar to natural wetlands as mitigation for project impacts (Hammer, 1996). There are
generally two types of constructed wetlands: subsurface and free-water-surface systems (USEPA, 1999; USEPA, 1993a;
Hammer, 1989).
Restored and enhanced wetlands are historical, naturally occurring wetlands that have been disturbed through filling,
dredging, water elevation changes, plant community alterations, and/or modifications to buffers surrounding the wetland
that impact the wetland characteristics or functions. Restoration of disturbed wetlands usually involves rehabilitation of
hydrologic conditions and reestablishment of vegetation (Mitsch and Gosselink, 2000). Degraded wetlands offer opportu-
nities for restoration and enhancement through the careful application and operation of them for water quality treatment.
However, this approach should only be attempted if the water quality of the wetlands would not be degraded, there was a
net benefit to the wetland, and it would promote a return of historic or natural conditions to the wetland (USEPA, 2000a).
In natural wetlands with low productivity, nitrogen and phosphorus are often limiting factors, and adding nutrient-rich
water can increase productivity (Mitsch and Gosselink, 2000; Ewel and Odum, 1984). Restoring wetlands is an effec-
tive strategy for reducing agricultural NPS nutrient discharge. These systems can remove 90 percent to 100 percent of
suspended solids, 85 percent to 100 percent of TP, and 80 to 90 percent of TN (DeLaney, 1995). A compilation of data
from 60 studies of 57 natural wetlands in 16 countries showed that 80 percent of the wetlands reduced nitrogen loading
and 84 percent reduced phosphorus loading. The mean percent change in nutrient load between water entering and
exiting the wetlands was 67 percent (SD of 27 percent) for nitrogen and 58 percent (SD of 23 percent) for phosphorus
(Fisher and Acreman, 2004).
Constructed wetlands designed to retain nutrients from wastewater can function similarly to natural systems. They have
similar physical and biological processes and the operation is more passive and requires minimal operator interven-
tion as compared to WWTPs (USEPA, 2000b). Planning and design considerations for building constructed wetlands
have been developed by USEPA (1999). Wetzel (2001) provides a summary of the fundamental processes in natural
and constructed wetlands. Both natural and constructed wetlands exhibit plant and microbial metabolism involved in
nutrient/pollutant uptake, sequestering, and retention that is highly dynamic on daily, seasonal, and long-term annual
scales (Wetzel, 2001; Kadlec and Knight, 1996; Ewel and Odum, 1984). Furthermore, the amount and concentration of
nutrient loading in uence these processes at all scales. Nutrient removal rates have also been shown to be very high in
some natural and constructed wetlands. A study of 50 years of treating wastewater by owing it through existing forested
wetlands in the Mississippi Delta showed that nitrogen and phosphorus were reduced by more than 90 percent (Day
et a/., 2004). A constructed wetland in France was reported to have removed 54 to 94 percent of TN from coke plant
wastewater (Jardinier et a/., 2001).
Though there are similarities between natural and constructed wetlands, there are also several differences. Constructed
wetlands often vary in the shape and structure from natural wetlands. Often, constructed wetlands are shaped to fit into
the landscape with other features such as roads, buildings, or mature vegetation. This "fitting in" can limit the ability to
create a natural-looking and -functioning wetland. Many of the studies of constructed wetlands use conveniently-sized
plots (e.g., mesocosms) that provide straightforward control of soils, plants, and water levels as well as in ow and out ow
controls, which ease measurement of water quality parameters (Dierberg et a/., 2002; Jing et a/., 2002). Additionally,
constructed wetlands often have engineered substrates composed of gravels or artificial liners, which affect the sub-
surface nutrient removal processes.
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Natural wetlands are typically higher in biodiversity, while constructed wetlands are typically planted with a few select
plants and occasionally are inoculated with microorganisms (Wetzel, 2001). This greater diversity often allows more
light to penetrate deeper into the water, increasing the vertical extent of photosynthesis and survival of microorganism
assemblages. The increased species diversity and productivity maximizes nutrient retention, recycling, and storage
(Wetzel, 2001).
Guidelines for constructing wetlands produced in 2000 identified more than 600 active projects using constructed
wetlands to treat municipal and industrial wastewater, as well as agricultural and stormwater sources (USEPA, 2000a).
Using these projects and wetland science, USEPA developed "Guiding Principles for Constructed Treatment Wetlands"
to develop wetlands that improve water quality as well as provide wildlife habitat (USEPA, 2000a). The document gives
guidance on planning, siting, designing, constructing, operating, maintaining, and monitoring of constructed treatment
wetlands. Other guidance documents on constructing wetlands have been developed and provide useful information to
consider when constructing wetlands (Davis, 2003; Moshiri, 1993; Cooper and Findlater, 1990; Hammer, 1989 and 1996;
Kadlec and Knight, 1996). USEPA also developed two technical assessments of different constructed wetlands: Free
Water Surface Wetlands for Wastewater Treatment: A Technology Assessment (USEPA, 1993a), and Subsurface Flow
Constructed Wetlands for Wastewater Treatment: A Technology Assessment (USEPA, 1999). These can help determine
the selection and design of an appropriate constructed wetland.
Some recent studies provided additional information on design and performance of constructed wetlands. For example,
interspersing open water with emergent vegetation appears to maximize NH4 removal efficiency (Thullen et a/., 2002).
Adding maerl (calcified seaweed) to a laboratory wetland resulted in 98 percent reduction in phosphorus (Gray et a/.,
2000). Wetzel (2001) suggests that all wetland treatment strategies should maximize physical contact and duration of
contact between water and microorganisms and periphyton. Periphyton growing on aquatic vegetation have been found
to be significant in their assimilation of nutrients (Dierberg et a/., 2002). The importance of submerged aquatic vegeta-
tion and periphyton in improving constructed wetland performance in removing nutrients was demonstrated in studies
in the Florida Everglades (Goforth, 2001). Research also indicates that the uptake and return of nutrients are separated
in time and occur on different temporal scales, which should be taken into account during the design and operation of
constructed wetlands (Tanner, 2001 a). A comparison of subsurface systems found that wetlands performed better at
removing ammonia when incorporating three design elements: no algae, longer detention times, and deep root penetra-
tion of emergent plants, rather than only one or two elements (USEPA, 1993a).
Even though natural and constructed wetlands have been used for water quality treatment for many years, there are
still gaps in knowledge on performance and design factors. Studies are still needed to better understand the chemical
and physical characteristics of various nutrient fractions in runoff as well as the nature of nutrients that remain after
passage through wetlands (Dierberg et a/., 2002). Other studies have suggested the need for a widespread measure-
ment program to provide a more detailed evaluation of wastewater treatment systems to identify variability and factors
contributing to variability (Szabo et a/., 2001). The nutrient removal rates and capacity in both natural and constructed
wetland systems need further investigation to allow identification and comparison of nutrient removal in a wide spectrum
of wetland types, scales, landscape positions, regional climates, geology, and nutrient inputs.
3.3.1 Related Outcomes of Constructed Wetlands
Constructed wetlands designed to treat water high in nutrients generate related beneficial and detrimental outcomes.
These outcomes provide additional advantages and disadvantages to using constructed wetlands as BMPs in a WQT
program that should be considered when selecting this BMP to generate WQT credits. Knight (1992) provides an over-
view of the ancillary benefits and potential problems with the use of wetlands for NPS nutrient discharge. These related
outcomes are discussed brie y and incorporated with other study findings.
Constructed wetlands can provide many benefits in addition to water quality treatment (Kadlec and Knight, 1996). These
benefits include: photosynthetic production; secondary production of fauna, food chain, and habitat diversity; export to
adjacent systems; and services to human society such as aesthetics, hunting, recreation, and research (Knight, 1992).
One of the key biological benefits of constructed wetlands is their ability to provide habitat for plants and animals. Many
plants and animals live in wetlands, and many periodically use wetlands as drinking sources, breeding sites, or foraging
areas. For example, a series of shallow ponds constructed to maximize NO3 removal in California had an average avian
specie richness ranging between 65 and 76 species per month, including both common and rare species. Wetlands
also provide a food source for animals such as nutria and muskrats; however, these species can consume much of the
vegetation and reduce the nutrient removal function of constructed wetland (USEPA, 1999).
A summary of 17 case studies located in 10 states found that constructed wetlands can provide valuable wetland
habitat for waterfowl and other wildlife (USEPA, 1993b). However, wildlife can sometimes be detrimental to the nutrient
removal efficiency of wetlands. For example, in a constructed wetlands near Chicago, a large number of carp were
found foraging and resuspending sediment, thus decreasing the performance of the wetland. These fish had arrived as
juveniles in the in ow and grew up in the wetland. In another example, a wetland constructed to remove nitrogen from
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municipal wastewater included open water habitat to attract waterfowl. Wintering waterfowl and colonial red-winged
blackbird (Agelaius phoeniceus) used the open water areas, but contributed a small amount (2.6 percent nitrogen and
7.0 percent phosphorus of mean daily loads from WWTP) to nutrient loading during November through March (Ander-
sen etal., 2003).
Using wetlands for nutrient treatment can have demonstrated additional water resources benefits within the wetland and
downstream. The use of a natural forested wetland in the Mississippi Delta for wastewater treatment over 50 years has
shown significant sedimentation and resulted in increased accretion rates (Day et a/., 2004). The results of the study
suggest that the application of nutrient-rich wastewater, and the resulting sedimentation, can also gradually increase
wetland elevations and counteract some of the negative effects of sea level rise on coastal wetlands.
Adding nutrient-rich water into natural wetlands has been demonstrated to increase productivity of woody vegetation,
measured as stem diameter growth, and growth of herbaceous emergent and aquatic vegetation (Day et a/., 2004).
The additional growth of emergent and aquatic vegetation contributes more to sediment accretion. This sedimentation
function also improves downstream habitat. Water typically ows slowly through both natural and constructed wetlands
because of their gentle gradient and vegetation. The slow ow allows fines to settle out or deposit on vegetation. Con-
sequently, fewer fines are transported downstream, benefiting fish. Fines in streams can fill interstitial spaces within
gravel substrates, reducing the quality of spawning success in fish.
In addition to improving fish spawning habitat, constructed wetlands can provide additional benefits by ameliorating ood
waters, storing water for multiple uses, and recharging groundwater (Feierabend, 1989; Slather, 1989; Knight, 1992).
Watersheds composed of 5 to 10 percent wetlands are capable of providing a 50 percent reduction in peak ood period
compared to those watersheds that have none. Therefore, constructed wetlands can be valuable in watershed manage-
ment strategies, especially in areas where wetlands have been lost (DeLaney, 1995). The effectiveness of wetlands is
determined in part by the location of each wetland in the watershed. In arid regions, the reuse of wastewater through
treatment wetlands can be especially helpful in serving to conserve water, provide habitat, recharge groundwater, and
maintain longer instream ows downstream (USERA, 2000a).
Wetlands built along shorelines of streams, lakes, and marine environments can help control erosion from ows, wind,
and shoreline uses. The erosion is largely controlled by the rooted vegetation established in the wetland, which disrupts
the ow velocities and binds the soil. Constructed wetlands positioned along shorelines need to be carefully designed,
constructed, and maintained to ensure in ow water is treated by the wetland before discharging to adjacent water bod-
ies (Hammer, 1992).
There are several direct human benefits possible from constructed wetlands. The improvement of water quality by
wetlands has been found to benefit human health by reducing disease-causing bacteria and viruses (Jing etal., 2002).
Wetlands remove toxic chemicals found in wastewater in addition to nutrients. Harvesting of wetland vegetation has
been used for the production of methanol (USERA, 1999). Constructed wetlands with public access and public use pro-
vide recreation, research, and educational opportunities. Public education has ancillary benefits of generating support
for water quality and watershed protection. Constructed wetlands have been used in combination with other treatment
mechanisms to provide safe drinking water (Elias et a/., 2001).
Even though there are many benefits from constructed wetlands designed to treat water quality, these wetlands can
also have detrimental outcomes. For example, the use of farmland to construct a wetland results in a loss of that land
for farming or another land use. Constructed wetlands located in other water bodies (i.e., wetland, stream, or lake) or
immediately adjacent to natural water bodies can negatively affect the natural water quality or quantity of these water
bodies (USERA, 2000a).This effect depends on the quality of the natural water body and the design of the constructed
wetland.
Constructed wetlands that attract wildlife may have a negative consequence. For example, siting a constructed wetland
near an airport might attract birds, which present a hazard for airplanes and the birds. Constructed wetlands can also
be a hazard to wildlife if they provide large amounts of habitat where many birds of various species can interact and
spread diseases. Attraction of wildlife could also lead to increased encounters with domestic animals, leading to direct
or indirect harm to both animal groups (USERA, 1999). As mentioned above, wildlife can negatively affect the nutri-
ent performance of a wetland through direct input of nutrients or remobilization of nutrients. If water input is episodic
or seasonal, the high uctuations in water level and potential drought periods could be detrimental for organisms that
reside in the wetland. Constructed wetlands can be directly harmful to organisms if the water quality is poor or even
toxic. For example, selenium has been found to bioaccumulate in constructed wetlands, leading to reproductive failure
in fish and aquatic birds (Nelson et a/., 2000; Lemly and Ohlendorf, 2002).
The building of constructed wetlands requires disturbance of soil and vegetation. Disturbed areas are prime locations
for colonization by invasive plant species, especially if sources are nearby. Additionally, nutrient loading of wetlands
can result in a shift in plant species assemblages, often seen as an increase in weed invasion at the point of ef uent
discharge (Chague-Goff et al., 1999). Consequently, constructed wetlands can provide habitat and opportunity for
spreading invasive species.
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Public health and safety may be compromised by constructed wetlands if they are not designed and maintained care-
fully. Wetlands can have odors that are unpleasant for neighboring communities. Odors in constructed wetlands are
typically associated with high organic loadings, especially near the inlet. Also, without safeguards, wetlands can pose a
safety hazard to visitors to the wetland. Constructed wetlands used to treat wastewater need to prevent human contact
with the untreated water, which could carry pathogens harmful to human health (USEPA, 1999). In some areas of the
country, dangerous reptiles, including poisonous snakes and alligators, could be attracted to constructed wetlands. A
USEPA study is examining if treatment wetlands are more or less likely to create risks to wildlife species than adjacent
natural wetlands (USEPA, 1999).
Another species attracted to wetlands that can be a nuisance or harmful to humans is mosquitoes. Studies of mosquitoes
have concluded that the number of breeding mosquitoes in treatment wetlands is not higher than in adjacent natural wet-
lands (Crites et a/., 1995). Controlling vegetation to create dispersed open water patches can result in reduced mosquito
populations by limiting mosquito refuge areas and increasing predation areas (Thullen et a/., 2002). However, another
study found that vegetation management within constructed wetlands conducted in autumn to stimulate denitrification
correlated with higher mosquito abundance than control wetlands lacking management (Walton and Jiannino, 2005).
According to a USEPA fact sheet (2004), as long as wetlands function as healthy ecosystems—i.e., are able to sustain
mosquito-eating fish, amphibians, birds, and insects—they are not uncontrolled breeding grounds for mosquitoes. In
fact, it was found that mosquito habitat was reduced by almost 100 percent and the Culex species of mosquito almost
eliminated after a degraded wetland no longer requires mosquito control measures (USEPA, 2004).
There are also potential negative impacts to air from constructed wetlands. Denitrification process within microbes
that occur in wetlands converts NO3 to N2O, which is released to the atmosphere and has negative effects on local
ground-level ozone (DeBusk, 1999). This process occurs in anaerobic conditions, typically below the soil surface. A
study of constructed wastewater treatment wetlands in Sweden showed that N2O emissions varied seasonally during
two years of measurements: large spatial and temporal variations were measured in N2O ux; the largest positive ux
of N2O occurred in October, and the smallest positive ux in July (Johansson et a/., 2003). The release of CH4 gas is
also a negative outcome of denitrification (Wetzel, 2001). CH4 gas emissions from wetlands can contribute to local odor
issues and add to greenhouse gas levels. Emissions of greenhouse gases (CH4 and CO2) were measured throughout
an annual cycle and shown to be positively correlated with water temperature in shallow wetland ponds constructed
for nitrogen removal (Stadmark and Leonardson, 2005). CH4 production was most pronounced from May to September
when NO3 concentrations were low. The study concludes that constructed nutrient removal ponds emit greenhouse
gases comparable to lakes in the temperate region.
Knight (1992) provides guidance on optimizing the appropriate ancillary benefits and avoiding undesirable side effects
while achieving primary nutrient control goals. Many of the benefits and problems with constructed wetlands can be ad-
dressed during the planning and designing process. Maintenance following construction of the wetland is also important
in prolonging and enhancing the nitrogen and phosphorus removal efficiency and ancillary benefits, while minimizing
detrimental outcomes. Thus, the design for constructed wetlands needs to provide access for maintenance.
There are several techniques to improving nutrient removal. For example, partial nitrification of swine waste water prior
to discharge to a constructed wetland increased TN removal rates (Poach et a/., 2003). Another study found that adding
iron to the substrate significantly improved phosphorus retention (Cerezo et a/., 2001). A model showed that increasing
nitrification rates in the summer and denitrification rates in the winter would improve nitrogen removal efficiencies. This
might be accomplished by increasing carbon supply in winter (Gerke et a/., 2001).
The selection of the appropriate plants for constructed wetlands affects the performance and maintenance of the wetland.
Floating aquatic systems are more affected by pests and cold temperatures and are more expensive to construct and
operate than surface- ow systems planted with emergent plants (Payne and Knight, 1997; Hunt and Poach, 2001).
Common plant species used as emergents include bulrushes (Scirpus sp.), cattails (Typha sp.), and rushes (Juncus
sp.). These plants are important in transporting oxygen from the leaves and stems to roots, providing an oxidized mi-
croenvironment in the typically anaerobic root zone of wetlands (Armstrong, 1964).
The juxtaposition of aerobic and anaerobic zones at the soil-water interface is important for nitrification when ammonia
is transformed into NO3 (Hunt and Poach, 2001). Thus, the amount of oxygen reaching the root zone affects the rate of
nitrification. Different plant species transport oxygen at different rates to this zone; therefore, plant selection affects the
performance of constructed wetlands at treating nutrients. For example, bulrushes have higher rates of oxygen transport
than cattails (Reddy et a/., 1989; Szb'gi et a/., 1994), and the sediment around bulrush roots was aerobic 30 percent of
the time versus 0 percent of the time around cattails (Szb'gi et a/., 2004). Even so, Wetzel (2001) suggests that rooted
emergent plants cannot be expected to aerate saturated sediments because the function of translocating oxygen to the
roots is to support the metabolic needs of the root tissues, not to oxidize the sediments.
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Although the results of some of the studies cited above suggest that certain plants may transport excess oxygen down
to the sediments, if very high levels of nitrogen removal are required from a treatment wetland, procedures that increase
oxidation of wastewater prior to entering the wetlands or designs to include open water areas might be needed to in-
crease nutrient removal efficiency (Hunt and Poach, 2001).
Removing accumulated emergent biomass and physically limiting the area available for vegetation reestablishment sig-
nificantly improved the ammonia removal efficiency. Limiting emergent plants mimics early successional patterns with
actively growing plants and results in interspersed open water, which also reduces mosquito populations by increasing
predation areas (Thullen et a/., 2002). Harvesting shoots may not be important for long-term nitrogen removal because
most of the nitrogen is removed through denitrification (Wetzel, 2001; Matheson et a/., 2002). Tanner (2001 b) found that
sediment containing high organic matter accumulated twice the nitrogen and six times the phosphorus than live and
dead plant tissue (Tanner et a/, 1998). Therefore, harvesting the above-ground portions of emergent vegetation might
provide only a small contribution to long-term removal of nitrogen and phosphorus from the system.
Because constructed wetlands mimic natural systems, they are, by design, naturally functioning, passive, and require
limited operational maintenance. However, the imitation of natural systems does not eliminate the need for maintenance
of constructed wetlands. The most critical element of maintenance is the quick identification and action when water level
adjustments are needed (USEPA, 2000b). Water level affects many of the processes occurring within the wetland and
the survival of aquatic organisms. Regular inspections are fundamental to identifying problems and taking corrective
actions, such as adjusting weirs or other water level control features (Kadlec and Knight, 1996).
Constructed wetlands have maintenance requirements similar to stormwater ponds, including hydraulic water and
depth control, inlet/outlet structure cleaning, grass mowing of berms, inspection of berm integrity, wetland vegetation
management, disease vector (e.g., mosquito) control, and accumulated sediment/organic matter management. Subsur-
face systems are prone to clogging and are limited in function by oxygen diffusion (USEPA, 1993a). Surface systems
may need extraction of built up sediments or vegetation that block ows (USEPA, 1999). Inspections may identify the
need to eliminate or control invasive or nuisance species (USEPA, 2000a). Sprinklers have been used successfully to
control adult mosquito populations in constructed wetlands because the sprinklers disrupt the water surface, affecting
ovipositioning (Epibare et a/., 1993).
Review of the related outcomes of constructed wetlands identified several research needs. The quantitative magnitude of
related benefits and detriments may vary greatly from one system to another (Knight, 1992). Therefore, related outcomes
need to be quantified and compared to different designs, regional variation, human values, etc. For example, studies are
lacking on odor associated with constructed wetlands used for water quality treatment, especially in comparison with
natural wetlands (USEPA, 1999). The causes, controls, and magnitude of odors as well as their community acceptance
would benefit from research.
There is additional need to monitor reference wetlands to compare performance of constructed wetlands and impacts
of external factors on wetlands. Monitoring should also include surrounding area as well as the constructed wetland.
The design and management of constructed wetlands lack complete understanding and incorporation of problems of
channelization, altered microhydrology at the spatial scale of microbes, and assimilation versus physical absorptive
retention (Wetzel, 2001). More research is needed on the temporal nature of nutrient removal by constructed wetlands.
For example, one study found nitrogen removal efficiency dropped from 79 to 21 percent in one year (Tanner et a/.,
2005). Removal efficiencies also dropped between the first and second year in experimental mesocosms (Hench et
a/., 2003). These changes in removal efficiency could be attributed to seasonality, wetlands maturity rates, or regional
factors. The use of constructed wetlands for trading programs could benefit from additional planning and understanding
about the long-term performance and fate of constructed wetlands.
3.4 Modeling Nitrogen and Phosphorus Removal by Wetlands
Modeling is used to quantify the performance of processes and to attempt to optimize this performance. Models are
useful for acquiring information about performance when actual measurement is prohibitively expensive (Johansson
et a/., 2004). The benefits of accurate models include improved designs, reduced monitoring, and predictability of per-
formance. This predictability could be used to define credits in a market-based WQT program. A predictive model for
constructed wetlands should be able to describe and predict wetland hydraulics, because this directly affects the treat-
ment performance of a wetland according to basic water quality modeling such as the k-C* model (Bojcevska, 2005;
Persson, 2005; Kadlec, 2000; Persson et a/., 1999; Wong and Geiger, 1997; Kadlec and Knight, 1996).
Although the physical and biological processes that drive wetland systems are complex, many mathematical models
have been developed to simulate nutrient removal in wetlands. Many of these models were developed by accounting for
hydrologic conditions and nutrient dynamics. A mathematical model was developed from studies of lowland rice fields
and can be used to assess the extent of absorption from the rhizosphere by wetland plants growing in coded soil,
incorporating important plant and soil processes (Kirk and Kronzucker, 2005). McBride and Tanner (1999) developed a
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mathematical model to simulate patterns of nitrogen removal that were observed in experimental studies of constructed
wetlands treating NH4-rich water. Brown (1988) developed a simulation model to predict water quality of out ow water
from natural and constructed wetlands. The model requires data input for wetland type, discharge rate, and concentra-
tion of nutrients in surface water in ow (Brown, 1988). Another mathematical model that simulates wetland hydrology
and nutrient-driven interactions between wastewater and wetlands was tested by comparing simulations with data
from a wastewater treatment facility (WTF) (Kadlec and Hammer, 1988). The simulation accurately predicted solute
concentrations, biomass growth patterns, changes in the litter pool, and soil accretion rates. Another two-part model
was developed by Dorge (1994) that contains a hydrological submodel and a more complex biological submodel. The
model was developed to determine the retention and removal of nitrogen in wetlands as water ows from cultivated
agricultural land through wetlands to aquatic systems. The model can be used to describe the transport and turnover
of nitrogen from fertilization through soil and groundwater to aquatic systems (Dorge, 1994).
Some models have focused specifically on plant uptake of nutrients (Langergraber, 2001; Mankin and Fynn 1996; Romero
et a/., 1999; Wegehenkel, 2000). Langergraber (2001) developed a model (CW2D) to simulate plant uptake of nutrients
in constructed subsurface ow wetlands relative to water uptake. The model was tested with indoor pilot-scale con-
structed wetlands. Langergraber (2005) tested the CW2D model for the portion of nutrient removal attributable to plant
uptake and concluded that it is possible to simulate plant uptake of nutrients in constructed wetlands with a model that
links nutrient uptake with water uptake. Another model, HYDRUS-2D, also models nutrient uptake by plants coupled
with water uptake (Simunek et a/., 1999). A mass balance method was used to quantify the performance of nutrient
storage systems in an experimental artificial wetland (Breen, 1990). In this simulation, hydrologic design to maximize
wastewater-root zone contact was determined to be important for treatment performance. Furthermore, uptake by plants
was found to be responsible for most of the nutrient removal, and plant biomass was determined to be the primary
nutrient storage mechanism. Other studies that included field measurements of nutrient uptake in constructed wetlands
often come up with the opposite result; plant uptake is a relatively small component of total nutrient uptake compared
to microbial processing (Hamersley et a/., 2001; Lin et a/., 2002; Stein et a/., 2003).
Simulations of natural wetlands have also been modeled. A model was developed specifically for riverine wetlands to
describe the interaction and processing of carbon, nitrogen, and phosphorus (van der Peijl and Verhoeven, 1999). The
simulation results showed a good fit to data collected on riverine wetlands in southwestern England. In a later test of
the model to study nutrient enrichment of a riverine wetland, results diverged from the field studies when the simula-
tions predicted a far greater role for nitrogen as limiting factor than the field experiments (van der Peijl et a/., 2000). The
lack of agreement between the simulation and the field experiments was attributed to differences in the environmental
conditions (e.g., weather and area measurements) between the field experiment and the computer simulation.
Field-scale simulation models have recently been practiced instead of intensely and expensively surveying farms or
conducting field trials for the myriad of conditions in a watershed (Johansson et a/., 2004). The advantage of field-scale
models is that they account for variability in land cover, soil, tillage, and drainage practices. An example of this type of
model is the Agricultural Drainage and Pesticide Transport (ADAPT) model. This model simulates the nutrient loads
and crop yields resulting from alternative phosphorus BMPs using variable management practices (e.g., crop choice,
fertilizer use) and climatological data (Johansson et a/., 2004).
Watershed modeling has been used to predict nutrient loadings (Arheimer and Wittgren, 2002; Gowda et a/., 1998). For
example, a study in Eastern Europe between Estonia and Russia used a large-scale geographic information system
(GlS)-based nutrient transport model over a 15-year period to model the change in nutrient levels caused by reduced
agriculture experienced by the region since the restructuring of the former USSR (Mourad and van der Perk, 2004). The
study applied the modeling approach developed by De Wit (1999, 2001), the PolFlow model, which used large-scale,
spatially variable estimates of sources, transport, and decay of TN and TP over five-year periods. The model consists
of three steps: estimating both diffuse (i.e., nonpoint) and PS emissions; calculating long-term hydrological uxes; and
modeling the transport of emitted nutrients through the soil, groundwater, and surface network.
Results from applying the PolFlow model were compared to measured loads and were found to coincide reasonably
well with one river and overestimate loadings for another with a smaller drainage basin. In the model, nutrient retention
within a drainage basin is simply modeled using a transport fraction factor that is determined by slope and discharge.
The study found that modeling was complicated by the transfer of nutrients from nonpoint emissions, which is strongly
governed by the retention in and periodic release from storages such as root zone, tile drains, ditches, channels,
substrates, oodplains, etc. Future research is needed to refine the quantification of this nutrient transport fraction.
Improvement to modeling nonpoint emissions was suggested by increasing knowledge about the spatial and temporal
distribution of various nutrient storage and uxes along pathways between the soil surface and water bodies (Mourad
and van der Perk, 2004).
In north Georgia, watershed-scale modeling is being used to estimate phosphorus loads for different NPS agricultural
practices. The Soil Water Assessment Tool (SWAT), based on the USERA Better Assessment Science Integrating Point
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and Nonpoint Sources software, is used for rural watersheds and can estimate phosphorus loads by calculating soil
loss. The model is calibrated using field samples and local watershed data. Calibration is conducted for two reasons:
to determine the parameter values that characterize the general hydrology of the watershed, and to find the parameter
values that describe phosphorus and sediment losses from agricultural sources and the effect of BMPs (River Basin
Center [RBC], 2003).
The DUFLOW model was developed in The Netherlands for simulating one-dimensional unsteady ow and water quality
in open channel systems (EDS, 1998). This model allows for the modeling of pollutant transport and defines processes
and pollutant interactions. A similar model was developed and applied to wetlands surrounding Lake Victoria, Tanzania,
to simulate the buffering process of wetlands and the capacity of individual natural wetlands to absorb sediments,
nutrients, and pollutants. This model estimated the impacts of inputs on water quality, quantity, and accumulation rates
in permanent fringe wetland and seasonal oodplain wetlands. This model included both nitrogen and phosphorus
compounds and 28 different parameters. The application of the model showed that there was seasonal ow from the
lake to the wetlands (Mwanuzi et a/., 2003).
A study in southwest Sweden was conducted to examine the applicability of the GLEAMS model to simulate the drain-
age discharge and nitrogen and phosphorus concentrations in the discharge water from a clay field with drain tiles
(Shirmohammadi et a/., 1998). The results indicated that GLEAMS was capable of simulating reduction of NO3 and dis-
solved phosphorus losses reasonably well, but there were no algorithms to simulate the particulate phosphorus losses
via drain tiles. Therefore, a submodel, "PARTLE," was developed and tested. These two models, combined, provided
reasonable estimates of particulate phosphorus loss via drainage through soil. The study concluded that considering
the impact of preferential ow and the ratio of annual drainage discharge to annual precipitation is necessary for proper
predictions of particulate phosphorus in structured soils.
Modeling fate and behavior of pollutants requires simulation of both transport and controlling processes such as sedi-
mentation, biomass uptake, sorption, etc. (Mwanuzi et a/., 2003). Modeling nitrogen ux in the lower Mississippi River
has been investigated by Mclsaac et a/. (2002). One model they examined accounted for 85 percent of the variation in
observed annual NO3 ux, but tended to underestimate high NO3 ux and overestimate low NO3 ux. Another model
that used water yield and net anthropogenic nitrogen inputs (NANI) accounted for 95 percent of the variation in riverine
nitrogen ux. The NANI approach accounted for nitrogen harvested in crops and assumed that crop harvest in excess
of the nutritional needs of the humans and livestock in the basin would be exported from the basin. The U.S. White
House Committee on Natural Resources and Environment (CENR) developed a more comprehensive nitrogen budget
that included estimates of ammonia volatilization, denitrification, and exchanges with soil organic matter. The residual
nitrogen in the CENR budget was weakly and negatively correlated with observed riverine NO3 ux. When the CENR
nitrogen budget was modified by assuming that soil organic nitrogen levels had been relatively constant, and ammonia
volatilization losses were redeposited within the basin, the trend of residual nitrogen closely matched temporal variation
in NANI and was positively correlated with riverine NO3 ux in the lower Mississippi River (Mclsaac et a/., 2002).
Crop yield simulation models that incorporate spatial information may apply to modeling nutrient removal in constructed
wetlands. Many of these models predict nutrient cycling such as nitrogen and phosphorus fertilization, nutrient transfor-
mations, crop uptake, and nutrient movement (Priya and Shibasaki, 2001).
Typically, robust and general models combine both empirical and mechanistic modeling. To gather large amounts of
data for empirical modeling, large databases have been developed. One of the most comprehensive summarization ef-
forts to date was the development of the NADB, funded by USERA (USEPA, 1994). Two versions of the database were
ultimately distributed. Version 1, completed in 1994, used an MS®-DOS database system known as Dbase III and was
the most widely distributed version. Version 2 of the NADB was built upon an MS® Windows Access database engine.
Collected data is analyzed using regression to determine relationships between variables. However, regression does
not necessarily indicate causality; thus, spurious relationships can be modeled. Research databases have been used
to validate and modify computer models (Humboldt University, 2000).
The first NADB database fell short of meeting its goal of providing sufficient information to optimize the design of treat-
ment wetlands (USEPA, 1999). The bulk of the entries in the revised USEPA-sponsored database (NADB Version II)
have been placed into a new database called the Treatment Wetland Database (TWDB). This web-based database adds
many additional treatment wetlands to the USEPA-revised database. While the emphasis is on constructed wetlands,
natural wetlands are also included in the TWDB database (Humboldt University, 2000).
Rigorous models for constructed wetland systems need to be developed by designing a comprehensive series of iterative
studies, collecting data based on quality-controlled specifications, and analyzing the relationships between design
features, environmental parameters, and performance. An assessment of current modeling efforts suggests that an
effective plan is needed for the design of studies that will provide a comprehensive understanding of the processes that
occur within constructed wetlands. The study design should include extensive, quality-assured, transect data at numerous
selected sites to capture spatial variation over an extended period of time to identify temporal variation. Using existing
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mathematical models of wetlands processes combined with the study data, an iterative model of complex systems can
be developed and used (USEPA, 2000b).
Modeling constructed wetlands is complicated by the complexity of the reaction mechanisms within these systems,
the difficulty in charactering the constituents within the in ow water, and the accountability of in uential physical and
external factors. Additional challenges include the ability to scale up, shortcomings in analytical and sampling methods,
and the capacity to verify models with long-term monitoring (USEPA, 2000b). Modeling is also problematic because
wetlands are highly ephemeral in capabilities and efficiencies for uptake and especially biologically-mediated retention
of nutrients and pollutants (Wetzel, 2001). Proper model selection is one of the most important steps in any modeling
exercise (Priya and Shibasaki, 2001). Many of the current design models for constructed wetlands rely on the assump-
tions of steady-state water ow conditions and first-order decay of pollutants. Studies have suggested that this is not
representative of field conditions (Kadlec and Knight, 1996; Persson et a/., 1999; Persson and Wittgren, 2004). Thus,
there is a need for more experimental data to further define how hydraulic patterns are affected under different envi-
ronmental conditions, both spatial and temporal.
Further research is needed to improve nutrient models, including detailed hydraulic investigations of full-scale wetlands,
simulations of outdoor constructed wetland systems, investigation of plant uptake models, improving the simulation tool
by accounting for substrate clogging processes, and developing experimental techniques to measure model param-
eters (Langergraber, 2003). More work is needed to adequately account for field environmental conditions in computer
simulations (van der Peijl et a/., 2000). Modeling nutrient removal by wetlands should account for delays in nutrient ow
pathways through groundwater. There are temporal lags in groundwater ow depending on the size of the aquifer extent
and recharge zone, as well as soil type and geology. Consequently, land-use management practices to reduce nutrient
loading to a watershed might not result in water-quality improvements for many years, especially if implemented on land
far from streams (Wayland et a/., 2002).
Additional incorporation into models of microbial and hydrological in uences on nutrient uptake could improve the pre-
dictability of nutrient reductions. Models tend to underestimate that most nutrients from in uent sources are assimilated
directly by microbiota (i.e., bacteria, algae, fungi) ratherthan plants and are intensively recycled amongst these microbial
communities, which coverall wetted surface in aquatic ecosystems (Wetzel, 2001). Channelization and variability in ow
velocity are among the greatest limitations to maximizing retention capacities of nutrients in wetlands (Wetzel, 2001).
If these channels and ow patterns are not included in models, then the predictability of the models is hindered by the
inadequate consideration of these patterns and their effect on absorption/adsorption rates. Advances in understand-
ing the hydraulic performance in wetlands can be gained by studying water ow patterns or hydraulic residence time
distributions obtained from tracer experiments (Persson, 2005).
3.5 Defining Nutrient Load Reduction Credits
A comprehensive review of WQT in the United States identified 40 trading initiatives in 17 states, 29 of which specifically
cover nitrogen or phosphorus (Breetz et a/., 2004). According to the information on WQT programs compiled by Breetz et
a/. (2004), potential NPS WQT partners include: new or expanding WWTPs trading with stormwater BMP retrofits, street
sweeping, land reclamation, surplus reductions from existing WWTPs, diverted ow from existing WWTPs, conversion
from surface to subsurface discharges, removal of poorly functioning septic systems, or wetland restoration.
The service area for WQT programs (i.e., the area in which trades are allowed) is most often defined by a watershed
or sub-basin boundary. A trading program in New York allowed trades only within the same basin, with the exception of
one WWTP that received credit for reduction in upstream phosphorus in a basin hydrologically connected to the basin
of discharge (Breetz et a/., 2004). Establishing a trading service area can be further complicated by political boundaries,
particularly in watersheds that cross state boundaries. Further division of hydrologically-related boundaries into trading
zones may be necessary in some area because of non-uniform mixing of nutrients in water bodies (Kramer, 2000).
Credits are often restricted to sources upstream from the point of discharge (Breetz et a/., 2004).
Building sufficient credit inventory to make a trading program cost-effective can be accomplished in areas that have
certain conditions favorable for the establishment of WQT programs. Favorable conditions usually include a wide varia-
tion in PS control costs, a large number of PSs, and the availability of low-cost NPS reductions (Kramer, 2000). The
seasonality of NPS reductions through implementation of BMPs is also an important factor to consider. The extent to
which the spatial and temporal patterns in wetland (or other BMP) nutrient removal performance match the spatial and
temporal patterns in load reductions needed by the PSs can determine whether NPS reductions would be appropri-
ate to offset PS discharges (Crumpton, 2006). Further organizational details that are required for a successful trading
program are outlined by Stavins and Whitehead (1996). These details include clearly defining responsibility for total
discharge; defining trading area; establishing legal authority for trades through rulemaking, legislation, and NPDES
permits; monitoring or statistical models to verify compliance; establishing procedures to reduce the costs of identifying
potential trading partners, negotiating trades, and program administration; encouraging public involvement to help speed
the regulatory process; and regular evaluation of the program for overall efficiency.
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Most BMPs used in WQT programs are general and are applicable to many agricultural operations; a few are specific to
certain farming activities. Example BMPs used in WQT programs include: livestock exclusions, buffer strips, constructed
wetlands, wet ponds, alternative surface tile inlets, cover cropping, roof gutters, filter walls and filter strips, manure
storage pits, conservation tillage, runoff control systems, settling basins, concrete barnyards, diversions, underground
outlets, livestock exclusion rotational grazing, wetland restoration, land set-asides, nitrogen application restriction, ma-
nure incorporation, sediment reductions through land acquisition, conservation easements, streambank stabilization,
development of silt basins, dry dams, terraces, grassed waterways, filter strips, and grade control structures (Breetz et
a/., 2004; Kramer, 2000).
Determining credit value for NPS operations is primarily based on getting agency concurrence of acceptable BMPs that
reduce nitrogen and phosphorus loading. Some agencies have developed a list of BMPs that are eligible to be used in
WQT programs (Idaho Department of Environmental Quality [IDEQ], 2003). The nutrient reductions from these BMPs
are usually required to be surplus, quantifiable, permanent, and enforceable.
Creating credits can be difficult in watersheds where agricultural sources are significant contributors to nutrient loads. A
common assumption is that agriculture can be a primary supplier of these credits; however, the willingness of farmers
to participate in such programs can be problematic for several reasons. Often, trading guidelines prohibit farmers from
selling credits when making legally required (e.g., by state regulation) land management changes3 or for which the farmer
has already been paid (e.g., green payments). These prohibitions reduce the ability of farmers to supply low-cost credits.
Because they require farmers create credits by implementing BMPs in addition to current practices and then demonstrate
that the BMPs do indeed reduce discharge levels (King, 2005). Many BMPs do not show direct improvements and are
not easily validated. Rahr, LBR and North Carolina have skirted this issue by assigning typical performance values to
specific BMPs. Applying additional BMPs and validating their effectiveness can be a risky endeavor for credit producers
because there is no guarantee that the time and money spent will generate more credits.
The need to establish a baseline nutrient load and show reduced discharge levels after BMP implementation creates
two additional obstacles for farmers considering supplying credits. First, in order to establish the baseline to quantify
marketable credits, an outside party must determine what nutrient-reducing land management practices and/or BMPs
farmers have already implemented.) This evaluation is something most farmers are leery about because it could gener-
ate questions regarding their justification for green payments or repercussions related to the legality of their land use
practices with respect to state requirements. Second, farmers know that their NPS nutrient discharge is currently not
regulated as much as PS discharge because NPSs can be difficult to measure, are weather-dependent, and can be
costly to control. By showing that they can create baseline information and then reduce their discharges below baseline,
they are actually demonstrating that NPS discharge is measurable and that perhaps it should be regulated the same
as PS discharge (King, 2005). Farmers are reluctant to participate in a program that could lead to additional regulatory
controls over their activities. The LBR program attempts to sidestep this issue through the approach for calculating nu-
trient credits. The baseline load of a NPS is first determined using the USDA-NRCS Surface Irrigation Soil Loss (SISL)
model. Credits generated by a BMP are calculated by subtracting the individual NPS share of nutrient reduction required
in the TMDL from the total nutrient reduction created by a BMP (baseline load multiplied by the BMP effectiveness ratio
[Breetz et a/., 2004]).
3.5.1 Measuring Nutrient Removal Performance
Estimating or quantifying existing NPS nutrient loads is necessary for calculating credits and for providing a baseline to
measure performance. Methods for measuring baseline conditions and performance of NPS nutrient reduction efforts
are highly dependent on the type of activity being conducted and the associated land use practices. Credits have been
granted for reductions in nutrient loads achieved through livestock exclusion, stabilization of eroding stream banks, con-
version of farmland back to oodplain, and vegetation restoration. These activities result in reductions in sediment and
soil loss as well as the associated nutrient reductions (Fang and Easter, 2003). Other programs have granted credits
for voluntary reductions as quantified by a "qualified soil and water conservation professional" according to standardized
procedures (Breetz et a/., 2004).
Where nutrient reduction data are limited and models contain uncertainties, as is currently the case of constructed
wetlands on a watershed scale, measurements of nutrient reductions can be taken to determine credits. Performance
can be measured as power (nutrient mass removed overtime) or efficiency (nutrient fraction removed overtime). Direct
measurement of nutrient reduction performance of a constructed wetland requires measuring the difference in nutrient
concentration between water in ows to and out ows from the wetland. The amount of actual nutrient reduction can be
measured using grab samples taken during the BMP operation. In the LBR WQT program, the measurement schedule
is determined in the trading contract for specific watershed-scale BMPs and regulatory guidance (ISCC, 2002).
Sfate land management requirements are relatively rare. North Carolina is an example of a state with land management re-
quirements in some watersheds.
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Measuring the nutrient removal performance of a BMP has advantages and disadvantages. An advantage of measuring
over calculating nutrient reduction is that it diminishes uncertainties, especially in terms of modeling nutrient loss, nutrient
removal by the BMP, and final nutrient loading in downstream water bodies. A disadvantage of measuring the effective-
ness of nutrient reduction is that it is very difficult and time-consuming in natural and restored wetlands because the
inlets and outlets often extend over relatively broad areas. It is much easier to measure the effectiveness of constructed
wetlands than natural wetlands because they can be designed with limited inlets, and outlets are often confined in order
to control water levels. The difference in concentrations of phosphorus, nitrogen, and other water quality parameters of
interest can be measured at the inlet and outlet, and can be taken as a direct measure of nutrient removal efficiency of
the wetland. However, measurement approaches need to account for diurnal, seasonal, and spatial variability in nutrient
retention efficiency (Wetzel, 2001). A review of 60 wetland studies showed that the duration and frequency of sampling,
as well as which nutrient forms were analyzed, in uenced in part whether the wetland appeared to reduce or increase
nutrient loading (Fisher and Acreman, 2004). Studies that included frequent sampling during high- ow events, or that
were conducted for more than one year, were more likely to indicate that the wetland increased nutrient loading, which
is the opposite of the expected result. Nutrients can be ushed out of wetlands during high- ow events, which results
in an increase of nutrients contained in water exiting a wetland. Wetland design can be used to mitigate or prevent this
from happening. Measurements need to be taken throughout the year in order to capture the variations in removal ef-
ficiency that wetlands experience overtime and seasons (Fisher and Acreman, 2004).
In addition to temporal factors, removal efficiency can vary depending on the position the wetland has in the landscape
and in the watershed. For example, wetlands high in the watershed may have limited opportunity to intercept nutrients,
and wetlands low in the watershed may have a ow-through rate that limits efficiency. Efficiency is also affected by the
geologic and ecologic conditions in the wetland, where different plant species or vegetation structure vary in their ability
to in uence nutrient removal (Mitsch and Gosselink, 2000). As described in the following section, WQT ratios can be
designed to account for the location of a BMP within a watershed.
3.5.2 Modeling and Calculating Nutrient Removal
Credits generated by implementation of BMPs can be modeled or calculated if it is too costly or infeasible to measure
the actual performance of the BMP. The first step in calculating credits is to determine the amount of nutrients produced
at a location. For example, to estimate the current phosphorus loads from cropland, formulas, such as the Revised
Universal Soil Loss Equation and SISL Equation, are used as the most accurate and simple method to estimate soil
loss from surface-irrigated cropland (ISCC, 2002; ETN, 2003). These tools can be used to calculate the tons of soil loss
per acre per irrigation season. Phosphorus reduction is compared against the phosphorus loads in baseline years used
for the TMDL (ISCC, 2002). As another example, reductions in phosphorus loads from cattle exclusion and rotational
grazing can be derived by calculating the volume of manure deposited and the associated phosphorus content and
delivery ratio (Breetz et a/., 2004).
Once the nutrient load has been calculated, the nutrient reduction from BMPs is needed to generate credits. One method
of calculating potential nutrient reduction is by estimating the average nutrient load reduction associated with a BMP.
Nutrient load reductions achieved through agricultural BMPs can also be estimated using field-scale water management
simulation models such as the ADAPT model. The ADAPT model can be used to model erosion and sediment transport,
which allows for an estimate of phosphorus load reductions from cover cropping, tillage practices, fertilizer applications,
crop rotation systems, and planting/harvest dates (Fang and Easter, 2003).
When modeling or calculations are used to estimate nutrient reductions, WQT programs tend to apply a discount to
compensate for the uncertainty associated with the effectiveness of the BMP, the accuracy of the modeling results, and
geographic variations in nutrient loads and environmental benefits. The multiplier, which is often expressed as a ratio
(e.g., 2.1:1 is the trading ratio used by the Neuse River Basin WQT program), is used by WQT programs to reduce the
number of transferable credits generated by a BMP. The trading ratio is designed to account for the level of uncertainty
associated with the methodology selected to calculate credits, and it is also often established for WQT between NPSs and
PSs to include a margin of safety to account for uncertainty in the determination of load reduction (Kramer, 2000).
Credits are also sometimes discounted using delivery ratios to account for location of the BMP project versus the loca-
tion of the nutrient source that is purchasing the credit. Location within the trading service area can affect credit value.
Delivery ratios were developed for the LBR program, which vary from 100 percent in riparian areas, to 20 percent within
% mile of the receiving water body, to 10 percent at distances greater than % mile from the receiving water body (Breetz
et a/., 2004). Ratio discounts range from 1.1:1 to 3:1. Overall, trading ratios are applied in WQT programs to ensure
that water quality in a watershed is protected and trades between sources distributed throughout a watershed result in
environmentally equivalent or better outcomes at the point of environmental concern (IDEQ, 2003). To minimize local
impacts or hot spots from PSs off-setting some of their nutrient discharges through trades, NPDES permits may place
a limit on the total amount of the nutrient discharge the PS may be offset through Another common approach to mini-
mizing the creation of hot spots, requiring prior approval from the organization that administers the trading program or
the state WQ regulator ensures the trade does not result in localized impacts to water quality.
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Other WQT programs have developed several ratios used in combination to address uncertainties. In Idaho, a River
Location Ratio accounts for the transmission loss of phosphorus occurring within the river system. Site Location Fac-
tors account for transmission loss due to phosphorus uptake by plants, water reuse, and the portion of phosphorus
that will bind with river sediments and settle out. Drainage Delivery Ratios are determined using a linear calculation
of phosphorus transmission loss in the subwatershed's main channels (IDEQ, 2003). Additional information on trading
ratios is also included in Section 4.3.2.5.
3.5.3 Assessing and Verifying Performance
The performance of BMPs needs to be assessed and verified to ensure a WQT program is successful. In the Idaho
WQT program, BMPs are certified as installed according to NRCS and meeting applicable laws and regulations. Once
the BMP is certified and operational, phosphorus reduction credits can be generated and traded (IDEQ, 2003). Monitor-
ing is another way to evaluate performance of BMPs. In Idaho they are used to demonstrate that the BMP is designed
and maintained properly, and the program guidance requires at least one annual field inspection to evaluate BMP per-
formance. Constructed wetlands are to be evaluated before and during the middle of the season of use (ISCC, 2002).
Another program suggests field spot checks should be performed for BMPs with a maintenance life of over one year.
The number of checks is determined based on an annual percentage of those BMPs (ETN, 2003).
Although protocols that produce reliable, quantifiable results have been established to monitor discharges from PSs for
most industries, similar protocols are not available to measure discharges from NPSs. Generating reliable, long-term
monitoring data of NPS discharges is one of the major challenges faced by WQT programs (Breetz et a/., 2004). Many
trading programs do not have systems for monitoring discharges from NPSs because it would be prohibitively expensive
and a long monitoring period is required to provide conclusive results (Breetz et a/., 2004; Jaksch 2000, Fang and Easter
2003). Periodic reviews of BMPs are often used in lieu of quantifiable monitoring. Some programs use a combination of
site-specific inspection at 5 to 10 percent of BMPs and continuous water sampling every eight hours at four locations
on a sub-watershed scale (Breetz et a/., 2004).
Models used to determine nutrient loads and nutrient reductions also need to be verified. A common method to verify
models is to calibrate them using local data. For example, stream ow conditions are monitored and grab samples are
collected to calibrate SWAT for ow and phosphorus removal rates. In addition, background levels of soil phosphorus
are determined by soil samples and used to calculate a soil phosphorus extraction coefficient, which is used to calibrate
SWAT. Other models can also be calibrated using daily data of groundwater, inter ow, and overland ow from differ-
ent land use and soil combinations. Several years of data are required for accurate calibration (RBC, 2003). Validating
models must consider spatial and temporal scales as well as data sources and manipulation (Priya and Shibasaki,
2001). Modeling nutrient fate and transport within a watershed is an extremely complex technical field, and a large
volume of information is available on various modeling techniques used in watersheds across the United States. As-
sessing the various methods being used to model nutrients within a watershed is beyond the scope of this paper, but
is an important research need.
3.5.4 Determining the Useful Life of Credits
Many programs establish time limits on the useful life of BMPs, after which it may no longer be effective. The length
of time a BMP can be used to generate credits, tends to be a function of how long it tends to be effective at removing
nutrients, with a margin of safety added (ETN, 2003). A comprehensive survey of trading initiatives found that structural
BMP credits were assigned a 10-year useful life, and non-structural BMP credits were typically good for 3 years (Breetz
et a/., 2004). A BMP's maintenance life and a margin of safety for uncertainties are used to determine the duration of
credits (ETN, 2003). Credited reductions are also sometimes limited in time to be contemporaneous with credit use
(e.g., the term of a NPDES permit) (Kramer, 2000).
BMPs have been given individual life spans to assure credit buyers that credits would be available and to assure credit
sellers that opportunities to market their credits persist for at least the designated life span of the BMP they choose to
implement. In some WQT programs, the life span assigned to BMPs re ected the professional judgments of scientists,
regulators, and field practitioners. In the LBR case study, constructed wetlands were originally assigned a 5-year life
span, but this was increased to 15 years based on discussion within a technical focus group (Koberg, 2006). In the Tar-
Pamlico case study, the credit life span for constructed wetlands is currently 10 years. The handling of credits that have
been banked, but not used within 10 years, is one of the issues participants in this WQT program are currently working
to resolve (Huisman, 2006). More research and discussion are needed to evaluate and determine the ecologically and
programmatically functional life spans for constructed wetland BMPs used in WQT programs throughout the United
States, the change in BMP performance over this life span, and the relationship of this life span and performance to
water quality credit value.
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4.0 Economic Literature Review
Traditionally, PS dischargers have three alternatives for managing their discharger liability: (1) meet allowances by
investing in additional control measures, (2) meet allowances by trading for WQT credits, or (3) evade regulations and
use legal and political processes to minimize enforcement penalties that are unavoidable (Kydland and Prescott, 1977).
Because direct action (i.e., items 1 and 2) has been expensive and financially ineffective, strategies involving avoidance
or liability transfer have become popular recently (King, 2005; Faeth, 2000).
WQT is a voluntary alternative for achieving regulatory compliance. It is a relatively new program, whereby parties can
meet their discharge allowances by trading with each other. In WQT, cost-ineffective dischargers buy nutrient allowances
or credits from cost-effective4 dischargers, who have earned them by voluntarily implementing BMPs for nutrient control.
By trading credits, parties reduce the overall cost of achieving nutrient reduction targets. In an ideal market, this process
minimizes the cost of nutrient abatement.
An established market or exchange provides the mechanism for WQT transactions. The regulator may play a third-party
role in the market, protecting the interests of the public by ensuring that trading does not lead to degradation of the
environment, and setting the ground rules for trading. At a minimum, the regulator must recognize WQT as a legitimate
alternative to discharge compliance.
Overall, economists, regulators, dischargers, environmentalists, and other stakeholders have advocated WQT as a way to
use markets to reduce the cost of nutrient compliance. For example, a simulated trade for the Idaho LBR trading program
estimated cost savings to be $10 to $158 per pound of phosphorus reduction using a sediment basin and constructed
wetland in series over PS controls (Breetz et a/., 2004). Furthermore, the Tar-Pamlico Basin Association (Association)
estimated potential costs at $7 million to achieve a comparable level of nutrient reduction that a $1 million investment
in NPS controls yielded (DeAlessi, 2003). The approach diversifies discharger alternatives for controlling nutrient with
less regulation, less cost, and accelerated compliance. This diversification allows for optimum utility of the watershed
without increasing natural resource risk. In all the case studies reviewed, regulatory oversight controls the process.
WQT is an attractive strategy for managing and reducing nutrient discharge. It presumes that PS dischargers will prefer
to meet their allowances by buying credits on the market if it is less expensive than installing and operating new controls.
It also presumes that NPS dischargers will elect to generate and sell credits by implementing and operating BMPs, if
risks and return on investment are favorable compared to other uses of the land.
As of 2004, more than 70 WQT initiatives have been set up in the United States, establishing several WQT trades
and pilot projects (Breetz et a/., 2004). USERA (2004) has simplified the task for future exchanges, providing technical
information for setting up an exchange, measuring equivalency of nutrient discharges, developing rules of exchange,
establishing trading baselines, and structuring liability transfers (see Section 5.0 for more information on the USERA
Water Quality Trading Policy).
Despite established market infrastructure and strong institutional support, nutrient trades have been relatively scarce to
date. However, some trades have resulted, especially PS-NPS trades characterized by high financial leverage. Scarce
nutrient credit supply from NPSs and lackluster credit demand from PSs are primarily responsible for this weak market
performance (King, 2005; King and Kuch, 2003). Incomplete economic valuations of WQT alternatives may lead to
hesitation to participate in WQT. Price should re ect the intersection of the supply and demand curves, which define the
relationships between how much a seller will supply and a buyer will demand for a given price, respectively. However,
several factors affect each of these relationships and thus the market efficiency. A more reliable approach to credit
pricing, based on thorough and cost-effective economic valuation accounting for risk, which will more accurately define
Cosf effectiveness refers to the cost of achieving desired outcomes in terms of relevant outputs, programs or administered
expenses. Cost effectiveness of an output or program is different than efficiency. The latter refers to output per unit of input.
Economic efficiency allocates resources to people who are the most successful at gaining social power. In the economist's
ideal world, the rich get richer and the poor get poorer... There is an assumption in economics that the market system handles
resource allocation in an efficient manner unless proven otherwise (Tietenberg, 2001; Nguyen et al., 2004).
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the supply-demand curves, is needed to enable traders to value their option to reduce their nutrient management costs
by WQT.
Based on a review of past initiatives, particularly those of the four case studies presented in Sections 6 through 9, this
section identifies the primary economic challenges to developing a robust WQT market involving wetlands and to set-
ting up these exchanges. Potential solutions to these problems are introduced and suggestions are offered to stimulate
the WQT market and accelerate nutrient reductions in watersheds and receiving waters. With the focus on the utility
of wetlands as a means to earn sellable credits, these challenges are not necessarily generalizations applicable to all
of WQT.
WQT provides an alternative way to quickly implement policy that includes NPSs and ensures a reduction in water nutrient
loads. Two strategies are available to the NPS dischargers: (1) function as status quo, discharging at accepted baseline
levels and (2) reduce discharges from baseline levels through BMPs, thereby generating tradable credits The selection
of a strategy involves an assessment of costs and benefits, accounting for risk. Only the second strategy provides NPS
dischargers with opportunity to invest in BMPs and WQT. Only the generation of credits by NPSs and the demand for
credits by PSs provide the environment for a trade. This does not mean a trade will be executed.
Agency policy controls the risk of degrading the watershed. As such, the value of WQT is well defined in terms of "overall
reduced pollution rate," (pounds/time) within concentration limits (mg/L), rather than the rate of economic value creation
(dollars/time). As a result, regulators supporting WQT only have to guide strategies that lead to constituent mass rate
reductions. Beyond that, regulators may also contribute to developing, implementing, and monitoring the market. The
implication is that reducing nutrient discharge for credit generation increases the services of ecosystems reliant on that
water, and thereby the potential to create economic value in the future.
In WQT, nutrient reduction is driven by discharge limits imposed on PS. The price of nutrient credits is in part determined
by the demand for and supply of credits. Economic valuation of strategic alternatives, i.e., accounting for risk aversion, is
a valuable metric for potential trading participants to decide whether to trade, and negotiating the terms and conditions of
the trade. Although a full economic valuation may encourage an active market, it is not critical for successful trades.
4.1 What Factors Determine the Cost of Creating a Market?
WQT requires establishing certain structures: (1) approved use of discharge credit trades to achieve compliance, (2) a
trading platform or exchange, (3) sources of supply and demand, (4) a pricing structure that accounts for liability transfer,
and (5) a governing body responsible for oversight and enforcement. Although Step 1 mandates regulatory involvement,
the remaining steps are plausible with varying degrees of it. Likewise, actual trading involves private transactions with
varying degrees of regulatory oversight.
A team of oversight and contributing agencies assumes most concept development and market development costs.
Individual and associated dischargers, independent investors, private and public grant institutions, and other enterprises
contribute as well.
Certain costs are usually incurred when WQT markets are developed and launched, as listed below. These are one-time
set-up costs, which may span several years. Once the market is operational, administration and governance costs are
embedded in transaction costs, as described in Section 4.3.3
• Concept review and approval cost
• Baseline assessment cost
• Objective-setting cost
• Allowance allocation cost
• Market development cost
• Pricing structure cost
• BMP development cost
• Stakeholder buy-in cost
Each of the selected case studies—i.e., Cherry Creek in Colorado, Rahr in Minnesota, LBR in Idaho, and Tar-Pamlico
River and Neuse River in North Carolina—demonstrate these cost structures (e.g., Breetz et a/., 2004; Jaksch, 2000;
Anderson, 2000; Kieser and Associates, 2004).
To cut costs and improve internal efficiencies, certain lead agencies hire dedicated staff for WQT market and permit
development. In the Rahr (PS) Malting Company trade, MPCA absorbed 85 percent of the dedicated staff cost. As the
WQT credit buyer, Rahr paid the remainder (Jaksch, 2000).
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4.1.1 Concept Review and Approval Cost
Agencies and/or dischargers interested in WQT thoroughly assess the viability of WQT in their jurisdictions, considering
watershed-specific issues, such as hydrology, geology, biology, ecology, economics, source distribution, stakeholder
interests, and so forth. The agencies engage local, state, and federal stakeholders potentially interested in the process
(e.g., USEPA, US Department of Fish and Wildlife Service). They explore the viability of forming teams of regulators
experienced in WQT, as well as agricultural, industrial, environmental, and other stakeholders.
The cost of completing this review is highly variable, and dependent on watershed-specific physical conditions, natural
resources, stakeholder views, agency positions, and other matters. For example, each of the four trades for Rahr required
concept review and approval, contributing to total transaction costs of $105,000 (Fang and Easter, 2003).
4.1.2 Baseline Assessment Cost
As part of concept evaluation to achieve a watershed's TMDL, agencies oversee field studies that assess the distribution
of nutrients in surface waters and shallow groundwater. Ecosystems, hydrology, biota, and other natural systems are
studied as well. In addition, field investigations and records audits establish or approximate nutrients discharge history
for PSs (e.g., NPDES-permitted dischargers) and NPSs (e.g., non-permitted agricultural, forested and urban land) in
the watershed.
In certain situations, validated information from detailed studies is needed to implement watershed management mod-
els, ecosystem models, land use models, or commodity models (e.g., timber production). For example, $300,000 were
spent to develop a special estuary model to track and predict the behavior of nutrients in the Tar-Pamlico WQT region
of North Carolina, (Gannon, 2005a). An association of prospective PS traders paid the cost to develop this sophisticated
model.
Environmental grants, subsidies, and special contributions might be available to offset most or all of the baseline as-
sessment costs, including those for model development.
4.1.3 Regional Water Quality Objective Costs
Regional watershed water quality objectives, such as TMDLs, provide the over-arching driver for WQT. These water
quality objectives can be expressed as constituent caps, step-down caps, fractional rate reductions, or other metrics
that are clearly measurable in space, time, and mass. When distributed to individual PS dischargers, these measures
become potentially tradable allowances.
Typically, the regulatory cost to set up and manage watershed discharge limits is built into existing regulatory duties.
However, in some cases, regulators undertake special scientific studies to establish the bioequivalence of nutrients
discharged to different parts of the watershed. Depending on scope, these studies can comprise simple calculations
or expensive field measurements and laboratory analyses. The studies are used to aid in fair allocation of allowances
in a heterogeneous watershed, and provide a balanced platform for trading water quality credits from different source
areas. The cost of such "equivalence studies" is described in Section 4.3.1.
Delayed promulgation of a watershed's water quality objectives, such as TMDLs, can add significant cost to WQT. As a
specific example, WQT markets were developed in a Maryland jurisdiction, but were only used when regional TMDLs
(and thus individual allowances) were imposed (King, 2005). Lacking a tradable commodity, buyers and sellers did not
appear. In the interim, regulators developed innovative command-and-control measures to encourage PS investment in
traditional wastewater treatment. Innovative subsidies were also offered to NPSs, for the use of BMPs. This procedure
led to nutrient reductions at a risk-free cost significantly higher than would be expected in WQT. The difference between
the use of WQT market compliance and the implemented programs is an avoidable opportunity cost5 of delayed TMDL
development.
4.1.4 Allowance Allocation Cost
Whether a constituent-specific cap is driven by a TMDL, total maximum annual load (TMAL), a remedial action plan,
or some other water management action plan, allocations must be distributed amongst dischargers. The total load for
a water body is generally determined as the sum of the loads from PSs and NPSs, accounting for projected growth,
seasonality, and a margin of safety. Monitoring and modeling typically determine the distribution of total load to individual
dischargers. Sensitivity analyses on various combinations of allocations factor into allocation development, with the aim
to collectively meet a desired load reduction (Michigan DEQ, 2002; USEPA, 1996; USEPA, 2002a). By allocating allow-
ances, regulators create a marketable commodity with an exchange value.
The opportunity cost of capital is the minimum rate of return, or "hurdle rate," which is used for discounted cash flow analysis
calculations.
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Allowance allocations are critical for creating a WQT program. However these costs are generally considered external
to the costs for developing and implementing a WQT program because the requirement to establish an allowance al-
location (TMDL, TMAL, etc) is present, regardless of whether or not a WQT program is established.
4.1.5 Market Development Cost
Market structures must be created to fit the stakeholder needs, physical situation, regulatory jurisdiction, local economy,
and impacted natural resources. Regulatory agencies may facilitate this process by establishing a marketable commodity,
proposing an attractive market framework, and retaining control of nutrient discharge risk. However, the onus for this in
a predominantly free market environment falls solely on the buyers and sellers. In the Cherry Creek case, 40 percent of
the Cherry Creek Basin Water Quality Authority's (CCBWQA) budget is assigned to monitoring, special studies, planning
documents, technical reports or memoranda, and administrative costs (CCBWQA, 2005). While some of those allotted
funds are used for previously discussed costs, they mostly fall into the market development category.
4.7.5.7 Creating the Exchange
Creating the exchange begs several questions, such as which kinds of trades should be allowed (e.g., PS-PS; NPS-
PS, NPS-NPS), and how to delineate the geographic limit of allowed trades. At a minimum, regulators must authorize
WQT as a valid alternative to internal control methods to satisfy discharge limits and confirm the necessary generation
of credits. In a free market, regulator involvement would cease there. However, regulators may structure the market
framework so that engaging in the market is attractive. Efforts are made to control the transactional cost of trading (see
Sections 4.3.3 and 4.4.2.3). In addition, the regulators may create and manage the trading organization responsible for
approving trades, protecting the environment, and administering the data generated by trading. The regulators could
also appoint and advise the governing body for the exchange, which is usually a Board of Directors, an independent
enterprise, an academic institution, a government organization, or other group.
Market structures are categorized as exchanges, clearinghouses, bilateral negotiations, and sole-source offsets6 based
on several criteria, including: (1) the commodity traded, (2) the market size, (3) the market structure, (4) the purpose of
the program, and (5) the governing authority for water quality (King and Kuch, 2003). As examples, the Cherry Creek
Basin program functions on a clearinghouse structure; the Rahr trade is a sole-source offset; the Association and
Neuse River Compliance Association (NRCA), each of which is issued a collective NPDES permit based on the sum of
members' allocations, create exchanges internally and function as an exceedance tax or group cap and trade program
within the watershed; and the LBR program in Idaho relies on bilateral negotiation. (Breetz et a/., 2004).
Ultimately, market structures must balance the needs for uid, low-cost trades that ensure environmental protection with
minimal oversight. Clear delineation of rights, responsibilities, and liability are essential considerations. The selection
of best market structure involves research, professional collaboration, optional fee consulting, and careful assessment
of stakeholder perspectives.
4.7.5.2 Creating Demand
Market designers create demand by assigning source responsibility for ef uent control and setting discharge limits. The
allowances should be measurable, and readily quantified or calculated by all parties.
Demand for WQT arises when the command-control cost of compliance is significantly higher than the trading cost of
compliance, accounting for risk. The wider the spread between control cost and traded cost, the higher the demand for
credits. Note, however that gaming the system7 becomes an attractive strategy when either: (1) regulations are weak or
The literature on this topic is confusing and contains references to credit trading, allowance trading, offset trading, emission
trading, pollution trading, etc. It also refers to different types of trading systems using terms such as clearinghouses or market
style or commodity-type trading as opposed to bilateral trades or centrally managed allowance offset contracts or sole-source
agreements. The taxonomy used here was presented in a recent paper by Richard T Woodward & Ronald Kaiser, Market
Structures for U.S. Water Quality Trading, 24 Rev. of Agric. Econ. 373 (2002), which does a good job of explaining critical dif-
ferences in these market structures (quoted verbatim from King and Kuch, 2003).
"Gaming the system" refers to when a dischargers perceive small expected environmental liability in failing to meet permitted
discharge requirements. These dischargers may elect to "game the system" as a preferred strategy. They invest to avoid, defer,
or dispute compliance requirements, accepting the expected cost of enforced compliance as a cost of doing business.
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absent, or (2) the cost of enforcement and penalties is low (King, 2005).8 Either of these conditions suppresses demand
for WQT, and for NPSs to sell credits.
As an example, strict regulations prohibiting any new discharges compel trading with NPS dischargers. Rahr had to
implement BMPs in order to build its own treatment facility. Without trading with NPSs, their only other alternative was
to continue paying fees to the WTF, sti ing growth.
Only three trades have been executed in the Cherry Creek Basin program, and water quality standards for phosphorus
remain in violation. In this case, WQT demand has been soft because the cost of command-control compliance has
been low, due to TMDLs that are achieved through affordable technology. More stringent load allocations would likely
improve water quality and stimulate trading.
Demand-side risk is an important factor in creating WQT credit demand and in credit pricing. As described below, re-
vocation risk, insolvency risk, and knowledge risk apply to WQT, but not to adding control measures. To some extent,
each risk suppresses demand. Accordingly, although regulations addressing these issues are not critical to WQT, they
should encourage trading.
• Revocation risk: Regulatory enforcement risk presents significant concerns to both buyers and sellers. A major
concern is that WQT schemes will not meet the requirements of the CWA in the future, if challenged. A CWA rul-
ing against WQT could negate or reverse credit sales, returning the compliance liability to the PS discharger. A
similar result could be caused by regulatory changes or rulings that revoke permission to trade nutrients as a way
to achieve compliance. A revocation would require the PS discharger to reassume compliance liability. Compliance
could require significant investment in technology, capital equipment, and regulatory relations over a long time. This
would be substantially more expensive than using WQT to comply with discharge allowances.
• Insolvency risk: This is the risk that an NPS trading partner becomes insolvent, and financially unable to meet BMP
requirements established by agencies. In this case, the PS discharger might have to take direct responsibility for
maintaining, monitoring, operating, and reporting on BMP activities at the NPS property. The relative cost of this
scenario is unclear, but certainly less than direct compliance through traditional command-and-control.
• Knowledge risk: The buyer may be responsible for implementation of a BMP on an NPS property. In that case, the
buyer assumes certain, limited risk by having to pay for practices of business and environmental compliance in
which they are not expert. In this area of exposure, the buyer hopes that the Seller does an efficient job managing
their BMPs.
4.7.5.3 Creating Supply
Supply is created when NPSs (and other low-cost dischargers) implement cost-effective BMPs, which reduce their
discharges below their allowances. In so doing, the NPSs earn tradable credits that can be sold or banked for later use.
Tradable credits are in surplus when supply exceeds demand, signaling that credit prices should decrease. Many fac-
tors in uence the supply of nutrient credits, including compliance risk, financial risk, the cost of the BMP, the expected
selling price (unserved demand) and transaction costs.
• Following is a list of risks that in uence the generation ortradability of WQT credits. The magnitude of these risks
depends on the site-specific conditions of the NPS, including discharges, allowances, receiving water conditions,
impacted ecosystems, business operations, NPS finances, regulatory jurisdiction, and impacted stakeholders. Revo-
cation risk: Likewise for the buyer risk premium, contractual enforcement risk presents significant concerns to both
sellers, as well. A revocation would require the NPS to maintain BMP obligations and liabilities without offsetting
(credit sale) contributions from PSs.
• Non-compliance risk: By joining a WQT program, NPSs accept regulatory audit and inspection of existing operations.
Despite their typically unregulated discharge, NPSs may be regulated for other facets of operation. The inspection
will determine if current operations meet practices that are already required by law. If not, regulators could cite the
facility for non-compliance. Thus, by joining a WQT program, a non-compliant NPS assumes the risk that inspec-
tions will identify liabilities that had been avoided previously.
• Subsidy and green payment risk: In conducting baseline assessments, regulators might evaluate how subsidies
and green payments are used to control or mitigate discharges at NPSs. This review could identify situations where
Certain dischargers may perceive small expected environmental liability in failing to meet permitted discharge requirements.
These dischargers may elect to game the system as a preferred strategy. They invest to avoid, defer, or dispute compliance
requirements, accepting the expected cost of enforced compliance as a cost of doing business. Perceived enforcement costs
might be high, including fines, penalties, imposed "best-available technology," dispute cost, and regulatory charges. However,
dischargers electing this strategy view the probability of enforcement and penalties as exceedingly low, offsetting the cost
exposure.
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funds are used inefficiently, resulting in additional regulatory obligations or loss of compensation. The risk is that the
net income from subsidies or green payments could be reduced with additional regulatory scrutiny or obligations.
The frequency or likeliness of it occurring is neither readily measurable nor reported.
• Discharger status risk: Most NPSs are unregulated or implementing voluntary discharge programs. By entering a
WQT program, these dischargers embark on a path that increases regulatory involvement in their operations. Once
tradable discharge allowance is definable, an NPS could become liable to manage nutrient loads as a discharger
named in a waste discharge agreement or permit. Thus, certain NPSs might risk losing their "non-regulated" status,
potentially leading to substantial future regulatory liabilities and costs. For example, the American Beef Cattle Asso-
ciation worries that a nutrient discharge baseline set by allocated allowances would be a disincentive for WQT. They
propose that most beef producers would prefer to set voluntary discharge limits (voluntary baseline), and gain credits
by exceeding them. Farmers would be encouraged to apply BMPs to generate credits and drive the market.
• Trade risk: This is the risk that NPS credits are not salable once generated on the WQT market, leaving the NPS
with a residual, uncompensated BMP risk or cost. This could happen if the NPS implements a BMP due to specula-
tion when the market is robust only to have the market lose its viability. The actual demand could fall so far short of
the predicted demand so as to preclude a sale. It could also occur if the contracted buyers could no longer afford
the credits.
• Performance risk: There is no guarantee that all BMPs will perform up to expectations. However, BMPs that turn out
to be expensive will be unmarketable, leaving an NPS discharger with the cost of operating the BMP (or discontinu-
ing maintenance and foregoing the possibility of selling credits) without offsetting contribution from a PS. In these
situations, the return on BMP investments may be low or possibly even negative.
• Litigation defense risk: Failing to manage nutrient loads or implement BMPs presents litigation risk to the NPS com-
mitted by contract. Advocates of public interest might sue NPS dischargers for failing to contain or mitigate known
or should-have-known nutrient discharges. This risk increases as the values of natural resources increases, and
special interests become more effective in using litigation as a way to leverage green behavior by NPS.
As with the effects of risks on demand, each of these risks may suppress supply. The structure of the WQT market
should aim to alleviate these concerns. Doing so at the outset or during WQT programs will encourage participation,
credit supply, and the benefits of trading. Agencies can reduce nearly all these risks when they structure the WQT
market programs by removing regulatory uncertainty, in uencing price, protecting discharger status and income, and
providing legal protections. Accordingly, although regulations addressing these issues are not critical to WQT, they
should encourage trading.
In one example, supply issues were blamed for lackluster trading in the Cherry Creek Basin market. Aside from the
credits for the Phosphorus Bank, phosphorus reductions achieved from BMPs were not eligible for trading if they were
funded by the CCBWQA, the government entity charged with administering and managing the water quality issues of
this watershed. Furthermore, additionally9 dictated that credits be generated from controls satisfying one of the following
criteria: (1) controls where there were not any previously, (2) modifications to existing controls to improve the reduction
capabilities, or (3) new controls to reduce phosphorus loadings to less than the NPS TMAL allocation (Breetz et a/.,
2004). Eliminating these as potential sources for trading has dampened the supply of nutrient credits.
4.1.5.4 Creating Pricing Structure
Depending on the market environment, regulators, prospective traders, and other stakeholders all may be responsible
for creating the broad pricing structure for WQT during market creation and initial trading. This structure is set by direct
negotiations, auctions, or by a permitting authority. Direct negotiations are used when buyers and sellers together de-
cide on the price of a credit for the specific trade. The trades for Rahr were priced in this way. This approach may be
inefficient for larger markets due to complexities of scale. Instead, several auction alternatives are available. Uniform
price auctions promote equitability in that a single credit price is determined through the bidding of buyers' and sellers'
bids and offers for credits. Once determined, the credit price is used for all transactions. Finally, the permitting authority
may set the price of credits in a reserve pool to sellers in default.
The authority-set price for credits in the reserve pool is greater than the market-set price for credits exchanged between
buyers and sellers. Reserve pool credits are to supplement the credits of a seller who would otherwise default on the
trade agreement with a buyer. The Cherry Creek and Tar-Pamlico programs offer examples of this special case of price
setting (Negotiation Team, 2001).
Additionality stipulates that any NPS offset that would have occurred regardless of the trading program cannot count toward
a trade. This prevents double counting by ensuring that a nutrient control activity counts toward only one objective if multiple
objectives are met (Fang and Easter, 2003; Jaksch, 2000).
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Private value is re ected in the buyer's cost of compliance (or avoided compliance) and the seller's cost of BMP-gener-
ated credits eligible for trading. The cost to create market-pricing structure depends on the type, size, and complexity of
the developed WQT market. New programs should draw lessons from previous programs in North Carolina, Minnesota,
Colorado, Idaho, and other states.
4.1.6 Acceptable BMP Cost
Regulatory lead agencies may be charged with identifying and listing BMPs that NPSs could use to generate credits. In
a de-regulated environment, the traders would have to identify appropriate BMPs; however, regulatory agencies would
still have to approve the chosen approach. In most cases, this list is extracted from a broader list of potential mitigation
technologies and strategies that have been used in site-specific instructions to dischargers. Initial cost assessments
may extrapolate from previous experiences or from literature. The first phase of the Tar-Pamlico cost assessment drew
from BMP development for the adjoining Chowan River basin (Research Triangle Institute & USEPA, undated). The
incremental cost for this activity should be modest unless special studies or extensive research are needed.
4.1.7 Stakeholder Communication Cost
Lead agencies may be responsible for identifying and engaging stakeholders at the WQT program level and individual
project level. However, this is often not the case, few states have led trading efforts. Most pilots have been bottom up,
with state agencies coming to the table as participants. Grants have supported most of these efforts. Obligations include
arranging education and public outreach, leading public hearings, addressing stakeholder concerns with appropriate
strategies, developing and maintaining communication channels, maintaining public records, and so forth. The regula-
tory cost of these services is relatively high at the outset of WQT market development. Project-specific costs for these
services vary, depending on the regulatory structure proposed and the stakeholder sensitivities and special interests
involved (Fang and Easter, 2003). The project-specific stakeholder costs are included as transaction costs, described
in Section 4.3.3, or are subsidized.
4.2 What Factors Determine the Cost of Creating a Credit?
The private cost of the party seeking to generate credits is the sum of three sub-costs: (1) the cost to create the oppor-
tunity by engaging trading parties, (2) the cost to implement the BMP, and (3) the cost to manage the BMP. Analysis of
WQT cost-effectiveness must considerthe sum of these costs, not just the cost of the BMP implementation, versus the
cost of alternative actions, i.e., PS control, gaming the system, or zero-growth (King and Kuch, 2003). Because credits
are marketable goods and services, the costs of creating credits may be estimated and used to guide credit develop-
ment and trading strategy decisions, a potentially daunting task in the absence of an established market.
The private benefit includes the increase in marketable value afforded to the seller and other responsible parties. Ex-
amples include improved land use (e.g., more efficient farming) and asset creation (e.g., higher property value).
Since BMPs leverage private investmentto create public benefit, a thorough net benefit valuation is appropriate to assess
the value of BMP strategy for: (1) selecting the BMP to implement, (2) obtaining stakeholder approval, and (3) valuing
credits in the marketplace. Such an evaluation is not critical and has yet to be thoroughly performed, but it could indicate
additional BMP value, thereby encouraging WQT.
4.2.1 Project Initiation Cost
Low-cost dischargers who seek to earn credits by implementing BMPs to reduce discharges may incur regulatory cost,
especially if a third party is not involved. Agencies may be involved in every step of the process, starting with an as-
sessment of the applicability and potential success of BMP projects under consideration. This can involve field studies,
baseline assessments, technical research, stakeholder communication, and negotiations with the discharger. They may
also support or directly pursue grant applications for funding, on the part of the discharger or the agency. Alternatively,
in a de-regulated environment, these tasks fall on the traders.
4.2.2 BMP Selection Cost
A free market requires dischargers to invest in the identification, evaluation, and selection of BMP alternatives. As market
regulation increases agencies take on an increasingly larger share of these responsibilities. Acceptable alternatives are
based on: (1) the physical and constituent conditions of the discharger and the watershed, (2) the available investment
budget, (3) the regulatory and discharger objectives, and (4) the project timeline. This process usually involves a short-
listing of BMP alternatives and some level of field testing. Analytical testing of system performance is an optional step,
aiming to optimize project design. Investments in formal work planning, permitting, documentation, risk communication,
and stakeholder involvement are inevitable and appropriate.
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The total cost of this phase of work can vary widely, depending on the complexity and size of the project, the diversity
of stakeholder interests, the risk of failed innovative technology, and the sensitivity of impacted ecosystems (private
and public).
4.2.3 Approval and Permitting Cost
The regulatory cost to review, approve, and permit proposed BMPs depends on the complexity of the program. Involv-
ing stakeholder participation and even public hearing(s) may add to these expenditures. Project-specific costs may be
wrapped into cost for typical regulatory activity.
4.2.4 BMP Implementation Cost
The responsibility to manage the cost of BMP implementation is typically borne by the PS without compensation, by the
NPS with compensation, or by a third-party entity. For example, cost management for Rahr's traded BMPs was managed
by a five-person board, with one member being an employee of Rahr, but otherwise independent.
This cost normally includes expenses incurred in the design, installation, and management of BMPs during construction.
Most BMPs are simple, and involve no one other than the discharger (e.g., relocation of livestock) or farm equipment
operators (e.g., change in tillage by tractor operator). The discharger maintains records of these BMP expenditures for
regulatory reporting, tax reporting, real estate appraisals, WQT credit pricing, and other purposes.
Private dischargers typically determine the cost of implementing BMPs. Once committed, these costs are sunk, re-
gardless of credits generated or trades made. On the other hand, the regulator (market administrator) values the BMP
investment from a public perspective, whereby they participate in the selection of BMPs. Their value metric is cost per
mass of nutrients reduced, which measures the effectiveness of BMPs before the application of a safety factor. This
value is calculated by dividing the cost of implementation ($) by the nutrient reduction achieved (pound).
The cost of BMP implementation can range widely. In the Tar-Pamlico case, values for agricultural BMPs ranged from
$1 to $80 per pound of nitrogen reduced from discharge streams. Similar values for wetland restoration ranged from
$11 to $20 (Table 4-1). More expensively, values for stormwater BMPs ranged from $57 to $86 per pound of nitrogen
removed from urban runoff (Gannon, 2005a).
Table 4-1 Nitrogen Removal Cost-Effectiveness Comparison
Practice
Agriculture
• Water control structure
• Nutrient management
• Vegetated filter strip
• Conservation tillage
Stormwater / Bioretention
Riparian wetland restoration
$/lb Reduced
(30-year life equivalent)
$1.20
$7- $9
$7- $8
$20 - $80
$57 - $86
$1 1 - $20
Source: Gannon, 2005a.
The owner of many BMP projects for Cherry Creek has been the CCBWQA, the government entity charged with ad-
ministering and managing the water quality issues of this watershed. Using three-year projections, BMP implementation
costs are separated into design, capital, land acquisition, and operation and maintenance (O&M).Their 2004 projections
totaled $9,691,000 for capital costs, $600,000 for land costs, and $243,000 for O&M costs. Water requirements were
also considered, but were not valued (CCBWQA, 2005). These costs were phased over three years.
A simulated BMP development forthe Idaho trading program estimated costs by breaking them down into capital, includ-
ing engineering, construction, contingency, land acquisition, and O&M. Capital was estimated at $3,004,000, including
a 20 percent contingency factor and $10,000 per acre of land. O&M was estimated at $145,800, including $71,800 for
annual O&M and $74,000 for harvesting wetlands plants every five years. Assuming a 30-year life span and a 3 percent
in ation rate, annualized cost for removal of TP was $118 per pound or $67,000 per acre. This simulated cost is very
high compared to the cost of constructing wetland systems for treating stormwater, estimated at $10,000 to $30,000
per acre (Zentner, 1995; Reed, 1991).
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The Rahr trades with four NPSs cost $250,000 (plus an extra $50,000 for a failed BMP) to implement. The cost of
credits was estimated based on the capital and O&M costs of the project, the estimated pounds of offset nutrients it
could deliver, trading ratios, and safety factors. Assuming a 20-year lifetime and applying an 8 percent discount rate, the
average cost of reduction decreases to $0.20 per pound CBODs and $1.56 per pound of phosphorus. The long-term
measures, such as conservation easements and re-vegetation, are the most effective of the BMPs because they provide
greater nutrient reduction with low investment. Furthermore, the BMPs are expected to remain effective for the same
amount of time overwhich the nutrient reductions are estimated, minimizing the uncertainties associated with the trade
(Fang and Easter, 2003).
4.2.5 BMP Monitoring Costs
Once BMPs are operational, the installing discharger is responsible for meeting permit requirements including, but not
limited to, uninterrupted monitoring, appropriate maintenance, organized data management, and timely compliance
reporting. The WQT process is available to compensate the NPS discharger for his costs for system installation and
these ongoing responsibilities.
Failure to comply can result in fines or penalties paid by either the NPS discharger (before trading) or the PS discharger
(after acquiring credits by trade). As an example, the Tar-Pamlico WQT market stipulates that the ultimate penalty for
non-compliance is reversion to Best Available Technologies discharge regulations (Gannon, 2005b).
Monitoring criteria may be judged by performance, i.e., how well the BMP reduces discharges, or by activity, i.e., that
changes to reduce discharges have been implemented. (King and Kuch, 2003). Costs will be negligible for simple prac-
tices, such as rearranging ranch grazing. Costs for network monitoring will be low to moderately expensive, depending
on: (1) the technology applied, (2) the size and density of the monitoring network, and (3) the frequency of monitoring
events. Capital costs for fixed monitoring devices can add to the costs significantly.
4.3 What Factors Determine the Dollar Value of a Credit?
WQT credits are private goods and services that have private value set by trader negotiation, and are subject to a few
adjustments that are made to protect public interests (environmental goods and services). The marketplace sets the
value of WQT credits, specifically: (1) the buyer and seller cost of compliance using non-trading strategies, and (2) the
difference between generating and transacting water quality credits accounting for risk. The dollar value of WQT credits
is unique to the trading situation, and dependent on many criteria. For simple agricultural BMPs, the cost of credits is
a function of: (1) the present worth cost to implement BMPs for an extended time period, (2) an equivalency factor,10
(3) a contingency for technical uncertainty, or "safety factor"11 designed to ensure non-degradation of natural resources,
(4) an "administrative factor,"12 designed to finance agency oversight of WQT, and (5) the number of credits generated.
Stormwater and other NPS credits are priced using more complicated formulae involving stormwater ows, the cost-ef-
fectiveness of nutrient management, nutrient reduction goals, project life span, drainage rate, land cost, and so forth. The
pricing structure for WQT is based on simple supply and demand for credits, within guidelines set by those responsible
for administering the market or by the market itself.
4.3.1 Equivalence
Water quality varies in space and time. As a result, the actual and potential human health and natural resource damage
or loss caused by discharges is site-specific. Therefore, the nutrient allowances should vary from place to place. As a
preliminary step in valuing credits, regulators establish a baseline discharge allowance that applies equally throughout the
watershed. Site-specific nutrient discharges and credits are normalized to this watershed baseline by applying equivalency
factors (multipliers) to measured rates. Discharges that are less harmful to the environment than the baseline will have
equivalency factors less than 1.0. Discharges that are more harmful will have equivalency factors greater than 1.0.
Equivalency factors are applied in trading, to normalize the risk of continuing discharge at one location in exchange
for reducing discharge elsewhere.
Establishing nutrient equivalency fortrading can be expensive. For example, the Rahr WQT case spent roughly $100,000
of regulatory, trader, and third-party consulting time to establish quality equivalency factors for discharges of malt in Min-
nesota (Fang and Easter, 2003). This case posed unique challenges to achieving equivalence. In particular, the traded
nutrients were not the same as the TMDL targeted constituent, requiring equivalence among phosphorus, nitrogen,
sediment, and CBOD (Jaksch, 2000). Diligent efforts used site-specific modeling to estimate ratios.
10 An equivalency factor is a multiplier to establish the environmental substitutability of PS and NPS loading (Jaksch, 2000).
11 A safety factor is a multiplier to account for a margin of safety.
12 An administrative factor is a multiplier to account for administrative costs associated with the trade.
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4.3.2 Establishing Offset Fees
Offset fees are the cost basis for trading, incorporating BMP cost, safety factors, administrative factors, and BMP ef-
ficiency in reducing nutrient. Following are descriptions of the components of these fees.
4.3.2.7 BMP Cost
BMP cost comprises seller investments made to design, permit, and implement a BMP that potentially generates credits
for trading. Note that, depending on the program, credits from certain BMPs may not be tradable, including those gen-
erated from practices that are required by law and practices that are funded by subsidies, green payments, or govern-
ment programs that do not involve WQT. This reduces NPSs' potential to generate credits (King, 2005). As presented
in Section 5.2, if a 2007 agricultural bill passes, it would indeed recognize subsidized BMPs as eligible for WQT, likely
driving more NPS participation in WQT.
The total cost to implement a BMP is the net present value of cash ow for: (1) the plant, property, and equipment
needed to construct the BMPs, plus (2) the operational, regulatory, maintenance, and replacement costs to effectively
run the system throughout its useful life, minus (3) relevant subsidies or green payments received, plus (4) depreciation
and other accounting benefits. The unit credit cost is the total BMP cost divided by the number of credits generated by
the process.
4.3.2.2 BMP Effectiveness
The effectiveness of BMPs in reducing nutrient discharges is an important component of credit value. Relatively ineffective
BMPs are worth proportionally less than effective ones, and this value impact is re ected in trading ratios, equivalence
factors and price. The BMP effectiveness is less than or equal to 1.0.
4.3.2.3 Safety Factors
A "safety factor" is a multiplier that is applied to offset the uncertainty or risk of degradation or other negative con-
sequences of WQT. Since each BMP and trade is unique, safety factors are unique to site-specific BMP and trading
opportunities. Within a watershed, separate safety factors might be developed for separate watershed zones, different
seasons, and constituent species. As such, safety factors often account for equivalency factors.
A risk-neutral trading opportunity would have a safety factor of 1.0, meaning the risk of compliance without trading is
the same as the risk of compliance with trading. In contrast, high safety factors are applied to WQT where the risk of
negative environmental effects is high, relative to compliance without trading.
Predictably, conservative (large) safety factors inhibit trading, by deeply discounting the value of the NPS credit to the
PS buyer. However, overly optimistic safety factors can lead to abundant trades that threaten the environment by allow-
ing too much PS discharge above limits. Thus, the regulatory challenge is to use safety factors to encourage trading
while protecting the environment.
Most safety factors are in the range of 1 to 2.5. Safety factors of 3 (or more) can suppress the market, because buyers
have to pay for three (or more) credits in order to acquire one credit. Nonetheless, the CCBWQA for the Cherry Creek
program, which sets a minimum trading ratio of 2:1, recently removed the trading ratio cap of 3:1 to stimulate more
trading with NPSs farther from the Cherry Creek Reservoir (CCBWQA, 2005).
4.3.2.4 Administrative Factors
Administrative factors are applied to baseline cost to cover the cost of setting the ground rules for the WQT program.
In the Tar-Pamlico and Neuse River Basin case studies, this value was 10 percent, i.e., 1.1:1 (Breetz etal., 2004). The
Tar-Pamlico program also applied a 200 percent safety factor to the 10 percent administration fee, creating a 2.1:1
"trading ratio" for purchase of nitrogen offset credits. The fee to purchase nitrogen offset credits in the Neuse River
Basin Nutrient Trading Program takes into account a required 30-year BMP life span, as well as land costs (Breetz et
a/., 2004; Gannon, 2005b).
4.3.2.5 Trading Ratio
The trading ratio is the number of credits that a buyer must purchase in order to receive one nutrient credit. It is a func-
tion of the safety and administration factors, such that:
Trading Ratio = (1+safety factor)* (1+adtmin factor)
Every WQT has a trading ratio. Nearly all these ratios exceed one because safety factors are usually significantly greater
than 1.0.
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As trading ratios increase, the demand for nutrient credits is reduced. Payoffs, in terms of avoided capital cost to the
buyer or return to the seller, become relatively small, compared to risks plus "transaction costs."13
4.3.2.6 Offset Fee
The offset fee is the present worth BMP cost times the trading ratio. As an example, the offset fee for the Tar-Pamlico
program in North Carolina considered uncertainty in BMP effectiveness and administration costs (Gannon, 2005a).The
base offset fee took into account farmers' capital costs, maintenance costs, BMP effectiveness, area affected, and BMP
life expectancy. BMP effectiveness values were based on a literature review that included empirical studies of conserva-
tion tillage, terracing, and buffer strip BMPs in the Chesapeake Bay. The offset fee also includes the 2.1:1 trading ratio
that re ects a 10 percent administrative factor and a 200 percent safety factor (Breetz et a/., 2004; Gannon, 2005b).
Within a program, evaluations of different BMPs should re ect their specific lifetimes. Tar-Pamlico credits for structural
BMPs were assigned a useful life of 10 years, while non-structural BMPs were assigned a credit life of 3 years (Breetz
et a/., 2004; Gannon, 2005b). Evaluations often analyze the sensitivity of lifetime impacts as a way to compare costs
per year.
4.3.3 Transaction Costs
Transaction costs may be incurred by the regulator and/or by the traders. These costs are built into the price of credits,
as a cost of doing business. Keeping transaction costs to a minimum is essential for robust trad ing, as these are bottom-
line expenses to a WQT strategy. Excessive transaction costs are cited as a primary reason for limited trading within
well-established markets and exchanges (Collentine, 2003; Fang and Easter, 2003; Tietenberg, 2001).
4.3.3.7 Agency Transaction Costs
Several regulatory expenditures are directly tied to the agency development, execution, and oversight of specific trades.
Trade-specific regulatory transaction costs are incurred for:
• Audit and verification cost: These costs are incurred when regulators confirm the site-specific baseline for trades at
the NPS facility. This work includes site inspection and confirmation of correct BMP implementation by the seller.
Sampling and analysis cost might be included.
• Administrative and consulting costs: Regulatory costs to track the status and performance of the trade, and provide
regulatory consultation to traders as requested. Included are regulatory costs incurred to confirm that trades adhere
to transaction standards for equivalency, additionality, and accountability.
• Trade oversight: These costs relate to obtaining regulatory approval for the trade concept and the preparation of
agreements and permits. This includes unbiased trust fund management costs assigned to the project and con-
struction management oversight.
• Monitoring and enforcement cost: Trade management, monitoring, and enforcement were trade-specific agency
duties in the case studies. These costs include, but are not limited to, direct measurement of discharges at PSs,
indirect calculation of discharges, or fractional discharge reductions at NPSs. Also included are costs for internal
tracking of discharges, credits, credit reallocations, computerized data, stakeholder communications, and external
reporting to state and USEPA.
• Stakeholder communication cost: The regulator incurs costs associated with communicating with stakeholders po-
tentially impacted by the proposed trade to gain consensus support for the trade. Included are costs for education,
public hearings, special meetings, expert consultation, presentations, and related expenditures.
The detail of agency transaction costs is often blurred, since certain trade support activities overlap with normal agency
duties. However, documentation usually presents the overall costs, which must be borne by credit traders. For example,
for the Cherry Creek program, applications cost $100 and a discharger must pay an additional $500 to cover costs
incurred by the CCBWQA to evaluate the request for credit withdrawal from the Phosphorus Bank. The cost to apply for
credits from the Reserve Pool, regardless of the number of credits involved, is $2,500 (Breetz et a/., 2004).
4.3.3.2 Trader Transaction Costs
In a free WQT market, many of the agency transaction costs described above, particularly trade oversight, monitoring
and enforcement, and stakeholder communication costs, fall instead on the traders. Additional costs that accrue directly
to the traders are proportional to their activities in the trade (Collentine, 2003; Fang and Easter, 2003). The buyer and/or
seller incur these trade-specific transaction costs:
13 If these transaction costs are borne by taxpayers in general rather than the parties involved in the offset contracts, they may
not inhibit trading. However, these transaction costs reduce the economic gains from trade regardless of who pays them and
they will affect the acceptability of trading (quoted verbatim from King and Kuch, 2003).
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• Broker costs: Expenses to find trading partner and secure an exchange. Brokers in WQT can include private enti-
ties operating under fee agreement or public agencies. The efficiency of brokering is directly proportional to experi-
ence.
• Legal and accounting costs: Both buyers and sellers require a certain degree of professional service consultation,
to ensure leveraged negotiation support and appropriate tax and financial management strategies. Additional legal
costs include liability management services and seller creditworthiness assessment, to mitigate loss in the event
of seller insolvency. Risk transfer instruments might be valuable in certain situations as well, necessitating the par-
ticipation of insurance or risk management specialists.
• Engineering consulting costs: Consulting scientists are typically used to advise traders during the course of trade
development and execution. These specialists provide traders with information that would in uencethe risk-adjusted
value of the proposed trade, from public and private perspectives.
As trading ratios increase, the price differential between buyers and sellers decreases, suppressing the demand side.
Payoffs, in terms of avoided capital cost (buyer) or offset BMP cost (seller) become relatively small, compared to risks
plus "transaction costs."
4.3.4 The Asking Price
The seller's asking price for one credit is the seller's PS offset fee plus the seller's share of transactional cost plus the
amount of profit the seller seeks for taking risk in implementing BMP and entering WQT agreements. Price in ation that
is built into the offset cost, i.e., the safety and administrative factors, is allocated to agencies responsible for managing
compliance, and is not distributed to the seller.
4.3.4.7 Minimum Selling Price
The seller's minimum selling price (MSP) is the minimum amount the seller will accept for selling a credit in a nutrient
trade. This amount is the present worth cost of implementing BMPs, plus a reasonable profit, plus seller's share of
transaction cost (see Section 4.3.3), divided by the number of credits sold. The minimum safety, administrative, and
efficiency factors established by agencies are applied to MSP to establish the lowest trading price that would be ac-
ceptable in a nutrient trade.
Sellers may expect to generate profit from implementing WQT when the returns are high relative to other uses of the
land. As a guideline, the level of profit should meet or exceed their opportunity cost of capital, or minimum rate of re-
turn. To the extent possible, sellers will build negotiable profit expectations into the price of their credits unless they are
motivated to implement the BMP for other reasons, e.g., their operations will benefit in other ways in addition to income
earned from implementing the BMP. For example, stream bank stabilization projects completed as a part of the Rahr
BMP projects was very valuable to the property owners whose land was being eroded away by the Minnesota River.
4.3.4.2 Seller Opportunity and Risk
NPSs and other prospective credit sellers commit capital to WQT programs in order to create value for their organiza-
tions. Participation presents risk and opportunity to value creation, however. Example risks include the potential loss of
subsidies, or assumption of discharge restrictions, increased regulatory liability, or negative cash ow. Representative
opportunities include improved land value, reduced liability, avoided cost of compliance, reduced operating costs, and
so forth.
Sellers should assess the risk and opportunity of WQT before committing to a WQT program. Sellers can use expe-
rienced WQT brokers, strong advisers, BMPs with precedent, and risk-transfer mechanisms to lessen the risks and
increase the opportunities of implementing BMP and trading water quality credits.
In ideal markets, investors build their cost of risk into the price of their goods and services. Typically, credit prices have
not been structured to compensate sellers for their risk in implementing BMPs and engaging in WQT, but clearly need
to be. Based on the literature reviewed and the examples provided in the case studies, not pricing credits to include the
cost of investor risk may be a reason that WQT supply and trading are suppressed.
4.3.5 The Bid Price
The bid price is the fully loaded amount a buyer is willing to pay to obtain a credit, considering the risk of compliance
by trading. Despite the role of regulations in establishing the market, traditional market factors, such as supply, demand,
and competition, strongly affect the bid price. Internal business factors are relevant as well, especially: (1) the cost of
the next-best long-term compliance alternative (e.g., command-control or gaming the system), (2) exposure to liability
(e.g., potential litigation), and (3) opportunity to create assets (e.g., Rahr; Fang and Easter, 2003). Chosen alternatives
will depend on the business attitude of the buyer. Some, focused on reputation and societal obligation, will not game the
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system. For them, the only alternative to compliance by WQT is command-control. Others, willing to take enforcement
risk, prefer to game the system.14
4.3.5.1 The Cost of Command-Control
Most PS dischargers comply with evolving regulations by adding or modifying discharge control measures. This strategy
is attractive because it enables dischargers to be in permit compliance (and operations status) and compliance cost at
low risk. Through trade and enterprise associations, PSs may be able to leverage their permit requirements.
Adding control measures is a relatively costly compliance strategy in terms of risk-neutral cash ow compared to costs
to implement BMPs for NPS. Depending on the permit requirements, expensive capital equipment, monitoring, and
regulatory reporting may be needed. Cost offsets, capital benefits, and other benefits may alleviate the financial burden
that these requirements pose for the PS. Special subsidies, grant relief, and tax incentives may be available to reduce
or offset these capital requirements. Capital investment realizes additional benefits including the improvement or addi-
tion of plant, property, and equipment assets. Finally, reduced regulatory and third-party liability may result as well. It
is important to quantify these sources of value when deciding whether to meet permit requirements by adding control
measures by WQT or by an alternate strategy.
4.3.5.2 The Cost of Alternative Strategies
Intuitively, discharge sources would likely first search for inexpensive ways to improve internally in order to avoid paying
another source to reduce discharges. In most cases, simple measures are implemented to reduce nutrient discharges
before long-term compliance strategies are adopted.
Buyers estimate the present worth cost of implementing their chosen alternative to establish a baseline for pricing water
quality. If the chosen alternative is to game the system, the buyer's estimate must include the cost to ultimately comply
plus the cost of implementing the gaming strategy, plus the uninsured expected (probable) liability of litigation defense,
regulatory enforcement, and other exposures.15
According to King (2005), the expected marginal cost of gaming relates negatively to the strength of the laws and en-
forcement and positively to the penalties for non-compliance. This would peg the MSP for WQT near zero, as gaming
would be the least-expensive alternate strategy. As a result, demand for credits would presumably be soft, weakening
the market despite well-designed exchanges for trading (King, 2005).
If the chosen alternative is command-control, the cost of compliance is readily estimated using traditional means that
include the value of assets at the end of their lifetime and financial benefits, such as subsidies or tax treatments. Im-
portantly, some WQT structures require that PS buyers pay NPSs "incentive fees" for discharges above the regional
cap. The rationale for this scheme is to encourage PSs to satisfy their discharge requirements, but if that were not ac-
complished, to provide funds for BMP implementation. For example, under the Tar-Pamlico WQT agreement (Anderson,
2000), the PS association is obliged to pay $13 per pound of nutrients exceeding the discharge cap to the North Carolina
Agriculture Cost Share Program, a pre-existing program administered by the Division of Soil and Water Conservation
(DSWC) that funds 75 percent of the capital costs associated with voluntary implementation of agricultural BMPs. This
structure, which is analogous to a penalty, motivates the PS dischargers to invest in their own remedies to stay within
allowances.
Comparisons between alternatives are based on the metric of expected (probable) net present value of cash flow. To
the extent possible, the value of strategic exibility of broad alternatives is included in these comparisons, such that
various designs of a BMP may be compared to various designs of a given PS end-of-pipe technology. Buyers commit to
compliance by WQT when the fully loaded cost16 of other options exceeds the fully loaded cost of WQT, accounting for
the time value of money, risk, liability, feasibility, efficiency, cash ow, and other important considerations of the buyer.
4.3.5.3 Maximum Purchase Price
A buyer's maximum purchase price (MPP) equals the fully-loaded cost to implement the least-expensive option divided
by the number of credits needed to achieve compliance. Water quality priced above the buyer's MPP will not be tradable
without special terms and conditions (e.g., indemnification) that create value for the buyer.
14 Gaming is a theoretical issue identified by economists, however this review did not identify literature regarding the extent to
which gaming is actually practiced and whether in practice this is an issue for WQT.
15 Reputation risk, which is difficult to quantify, is an important aspect of gaming strategy. Many dischargers resist the temptation
to "game" the regulatory process to protect their reputation from discredit, even when the expected costs of additional controls
are significantly greater than the penalties associated with gaming the system.
16 In this use, the "fully loaded cost" is the present worth sum of all known and potential direct and indirect costs, liability, and as-
sets that would be caused by the implementation of strategy, accounting for uncertainty (risk). Uncertainty and risk are not the
same thing.
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Quantifying MPP should account for strategy risk, transactional cost, and the time value of money. The importance of
accounting for risk is apparent in comparing strategies, such as "additional control measures" (not risky) with "gaming the
system" (highly risky). The selected strategy should not re ect the regulatory cost to comply, but rather the discharger's
perceived least cost to manage his regulatory liability (which might involve non-compliance cost, litigation defense, or
liability transfer expense).
In some cases, the MPP is based on asset-driven considerations. For example, Rahr was willing to pay $250,000 to set
up a trust fund dedicated to implementing BMPs because it had no choice but to trade with NPSs. Otherwise, it would
not have been allowed to build its treatment facility at all, thereby hindering its growth. Furthermore, cooperating with
the community and environmental organizations served to elevate its social reputation.
4.3.5.4 Value Created by Trading
NPSs can create value over and above the value of mitigating nutrient discharge compliance liabilities by implement-
ing BMPs. Such value can include social benefits, increased property values, decreased liabilities, if any, unrelated to
compliance or WQT, improved cash ow or NPS net worth, and other private benefits that accrue to the NPS. These
values are quantified in terms of explicit (short-term) and continuing (long-term) value, discounting cash ow at a rea-
sonable rate of return.
The owners of land at two of the BMP sites that Rahr funded in its trade reaped the added benefit of controlling severe
bank erosion that had threatened their property. Since 1988, the property owners had been trying, unsuccessfully, to
gain financial means to control the bank erosion. Rahr accomplished for them what they had unsuccessfully tried to
fund for nearly a decade (Breetz etal., 2004; Fang and Easter, 2003). Many of the Cherry Creek BMPs have improved
the quality of the Cherry Creek State Recreation Area (CCBWQA, 2003a).
4.3.5.5 Avoidance Strategy: Game the System
Certain dischargers may perceive little expected environmental liability in failing to meet permitted discharge require-
ments. These dischargers may elect to "game the system," or evade compliance, as a preferred strategy. They invest to
avoid, defer, ordispute compliance requirements, accepting the expected cost of enforced compliance as a cost of doing
business. Perceived enforcement costs might be high, including fines, penalties, imposed "best-available technology,"
dispute cost, and regulatory charges. However, dischargers electing this strategy view the probability of enforcement
and penalties as exceedingly low, offsetting the cost exposure. Due to the covert nature of this activity, the frequency or
likeliness of it occurring is neither readily measurable nor reported. Given the $25,000/day fines and reporting require-
ments NPDES permit holders are subject to, the application of this strategy by NPDES permit holders may be limited,
but there is no literature to support or refute this conclusion.
4.3.5.6 Buyer Risk Premium
It is important that buyers account for their risk attitude, especially risk aversion, in establishing MPP. Particular risks of
concern, as described in Section 4.1.5.2, include revocation risk, insolvency risk, and knowledge risk.
4.3.6 Minimum Selling Price
In WQT, the MSP is the minimum amount the seller will accept for selling a credit in a nutrient trade. Typically, it would
consider the seller's costs to generate one credit (cost to generate credits divided by credits generated, or $BMP), the
expected risk premium (r), the unit credit value created from the BMP divided by the credits generated, and the expected
profit (p) calculated at a reasonable opportunity cost of capital. Following is a general formula for MSP:
MSP = ($BMP*(1+r) + $Val} * (1+p)
MSP does not include costs that are beyond the seller's control and that do not accrue to the seller, such as regulatory
upcharges re ected in "trading ratios." These price in ations concern the public value (cost) of strategy, and they are
allocated to those who manage the trade and BMP implementation. BMPs can also create value by increasing sellers'
assets, such as building the value of real property. In this model, transaction costs are split, and not part of the MSP.
4.3.6.7 BMP Cost
BMPs are calculated in discounted cash ow, including all costs incurred by the seller, regulator, contractors, technical
consultants, and professional advisers. Sellers should include WQT subsidies they receive in calculating their BMP
cost and MSP. However, buyers and sellers would negotiate the amount of these subsidies that would be included in
the terms of a trade.
The offset fee for the Tar-Pamlico program in North Carolina accounted for administration costs and for uncertainty
in BMP effectiveness (Gannon, 2005a). The offset fee was refined when the Phase II agreement was developed. The
base offset fee takes into account farmers' capital costs, maintenance costs, BMP effectiveness, area affected, and
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BMP life expectancy. BMP effectiveness values were based on a literature review that included empirical studies of
conservation tillage, terracing, and buffer strip BMPs in the Chesapeake Bay. The offset fee also includes a trading
ratio that re ects a 10 percent increase for administrative costs and a 200 percent margin of safety (Breetz et al., 2004;
Gannon, 2005b). The offset payments made to the Agriculture Cost Share Program are used to fund voluntary BMP
implementation (75 percent state, 25 percent producer) and pay for staff resources to track and target contracts and
verify compliance.
4.3.6.2 Seller Risk Premium
Sellers must assess program risk, as described in Section 4.1.5.3, before exercising the option to develop BMPs for the
purpose of WQT NPSs must assume certain roles and responsibilities in participating in the program. Most outcomes
of these commitments will be worse (risky), or better (opportunistic), than the current situation.
As an example, some believe that regulated PSs do not compete equally (on a cost basis) with NPSs, which use sub-
sidies and green payments to implement voluntary programs. They argue that certain actions should level the compli-
ance "playing field," including (1) shifting more responsibility for nutrient reduction to NPSs; (2) reducing subsidies; or
(3) regulating PS and NPS dischargers equally.
Offsetting opportunities, such as the chance to improve land value or reduce operating costs, are present, also. We
infer that risks exceed opportunities for most BMPs for three reasons: (1) the price structure for credits is fixed in some
programs, such asforthe clearinghouses for the Long Island Sound, Tar-Pamlico, and Neuse River programs, and there
is no way for the investor to recoup the cost of taking risk, (2) most WQT benefits and opportunities accrue to the public
(watershed), and (3) most WQT costs and risks accrue to the private investor (discharger). The inability of investors to
generate return on their investment while taking risk explains why many BMPs remain to be undertaken.
Ideally, investors would build risk-related costs into the price of goods and services. However, in the WQT markets re-
viewed, the third-party regulator set credit prices using established nutrient reduction cost and site-specific contingency
factors. The contingency factors represented public interests (regulatory cost, non-degradation cost, equivalency cost).
Contingencies re ecting private interests, such as program risks to the seller and investor, were not accounted. In a
free market, in which transactions occur directly between buyers and sellers or are facilitated by a broker or aggrega-
tor, the price of credits would depend on traditional market forces: supply and demand. The LBR project is structured in
this way: however; no trades have occurred. Thus, in theory, WQT credit prices have been artificially suppressed. This
should stimulate PS demand and encourage trading. However, it should also suppress supply, as NPSs will be reluctant
to invest in the WQT market if their net risk is significant.
4.3.6.3 Profit
Sellers may expect to generate profit from implementing WQT, especially if the risk they assume (Section 4.3.6.2) is
not offset by value created. As a guideline, the level of profit should meet or exceed their opportunity cost of capital.
A minimum of 10 percent is reasonable for most businesses. To the extent possible, sellers will build negotiable profit
expectations into the price of their credits.
4.4 Challenges and Gaps
It might take substantial modification of views to better understand the economic value that public and private interests
may generate by managing nutrients with WQT. Immediately needed are thorough economic valuations of strategic
alternatives that involve WQT. These valuations will enable decision makers and policy makers to quantify the value of
investing in WQT as a discharge management strategy of choice.
4.4.1 The Perspective Problem
WQT involves four essential stakeholders, each with his own interests, concerns, challenges, and gaps: (1) the buyer,
(2) the seller, and (3) the regulator, and (4) special interests and other stakeholders. The buyer and seller are concerned
with the financial risk and return of private transactions involving WQT. The regulator is concerned with protecting public
values in natural resources, i.e., enforcing non-degradation and conservation of natural resources such as water, wet-
lands, habitat, and species. Other stakeholders may in uence the regulators, who in turn will in uence the market.
Importantly, each stakeholder perceives different gaps in the current WQT exchanges, policies, programs, and transaction
structure. These gaps should be addressed in order to achieve a smoothly functioning and robust trading marketplace.
To complicate this challenge, differences from program to program, because of the need to tailor them to the specific
needs of the stakeholders within the watershed, creates potential for discord or potential litigation.
4.4.2 Challenges to WQT
Many established WQT exchange programs are relatively inactive. The challenges appear to lie not with the develop-
ment of exchanges, but with the viability of trading as a cost-effective mechanism of liability transfer between buyers
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and sellers. Economic trading challenges suppress WQT by making the risk-adjusted net economic value of trading
less attractive than alternate compliance management strategies. Four economic challenges threaten the development
of robust, sustainable WQT programs because they reduce the discounted cash ow return on investment (DCFROI)
of trading. These are: (1) simplified modeling of natural system impacts, (2) costly environmental protection, (3) high
transaction costs, and (4) ill-defined property rights. These challenges hinder efficient and fair deal making, usually
because they make investing in WQT strategy risky to the buyer, the seller, or both.
4.4.2.7 Simplified Modeling of Natural System Impacts
Most problems are analyzed as simplified forecasts of natural system behavior in the presence of nutrients. In reality,
nutrient discharges impact a complex web of interconnected ecosystems, hydrologic systems, biosystems, geologic
systems, and other natural conditions that evolve overtime. Even with seemingly simple scenarios, such as a bilateral
trade between a PS and an NPS utilizing wetlands downstream, the system is still complex in terms of reaching equiva-
lence between the spatially and temporally distinct discharges.
Continuous time modeling and analysis of nutrient impacts to complex natural systems is a daunting task. This ap-
proach allows the mapping and analysis of meaningful cause-and-effect relations within the natural environment and
the nutrients that affects it. Such analyses identify the total system cost and value of strategy, accounting for feedback
behavior among system components, including unintended consequences and counterintuitive behavior. They provide
platforms for real-time testing of new and evolving conditions, on a periodic or event-driven schedule.
In addition to the complexities of executing a single trade (quantification, ensuring equivalency, etc.) between a PS and
NPS, BMPs usually produce a variety of interlinked private and public; market and non-market values. For example, the
size of a wetland (e.g., private investment) not only delivers value in terms of water quality, it also provides ood control,
fish habitat, erosion control, recreation opportunities, etc. (e.g., public benefit, when used). This "non-market" value is
not accounted for in the price for a water quality credit. However, if implementation of BMPs, such as wetlands is to be
encouraged, a strategy that thoroughly accounts for public market value is needed. This could results in the following
possible outcomes: a multiple market system whereby a landowner is able to sell or otherwise gain compensation for
the other ecological services provided by a BMP, or a more complete understanding of the multiple ways a landowner
will benefit by implementing a BMP on their property, in addition to the income from selling water quality credits.
Incorporating public market values in decision analyses would allow traders to more accurately quantify and report their
return on investment in WQT. This would provide important information that would increase trading and market support
among NPS.
4.4.2.2 Expensive Risk Factors
Everything that is not known and provable is uncertain. This includes all future events. Quantitative analyses deal with
uncertainty by: (1) assuming it away, (2) assuming median values, (3) estimating to conservative values, (4) estimat-
ing to optimistic or best-case scenario values, (5) estimating using multiple experts, and/or (6) calculating "expected
values." Every calculation that includes uncertainty assumes the risk that the future will be worse than calculated, and
the opportunity that the future will be better than calculated.
Each uncertain variable carries some risk of inaccurately estimating its value. Together, these risks compound the estima-
tion risk of the overall outcome of concern. The default approach to evaluating the performance of a complex system is
to make assumptions that simplify the system and to include contingencies to account for risk of inaccurate estimates.
As a result, behavioral models are replaced with simple formulas. This process does not account for the in uence of
underlying variables (e.g., seasonal precipitation on peaking ow rates and reduced residence time of nutrients in riv-
ers). Averaging reasonably approximates some of this variability. Other rate changes are more difficult to assume, such
as increasing nutrient removal efficiency with evolving wetland ecosystems.
Uncertainty of future events is quantified by mean or conservative assumptions without calculation of the potential
impacts of under- or over-estimation. As a result, calculations of values for a WQT strategy are filled with arbitrary as-
sumptions, guesses, and/or estimates of what the future may hold. Regulators tend to use aggressive safety factors to
offset their lack of knowledge about how the polluted watershed system will perform given all complexities and uncer-
tainties (e.g., Breetz et a/., 2004). Thus, WQT credit asking prices are often in ated beyond the buyers' willingness to
pay, suppressing demand.
Agencies are charged with protecting the public trust, specifically the human, environment and natural resources that
are directly and indirectly impacted by nutrient discharges. They aim to protect the public from trade risks that are as-
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signed neither to buyers nor to sellers.17 Lacking quantitative methods for this assurance, agencies apply risk factors
to calculations of TMDL and other discharge limits. Necessarily, these factors are conservative to the extreme, re ect-
ing the most risk-averse stakeholders in the public trust. This conservative risk management has the effect of in ating
market prices and may in turn prohibit trading. The challenge is thus in balancing the protection of public interests and
stakeholder concerns. A quantitative method of finding this balance and tools to achieve it would allow for a reduction
in risk factors to a level that still benefits the public without overwhelming the market. As a result, the trader's return on
investment would increase, thereby encouraging more trading.
4.4.2.3 High Transaction Costs
WQT transaction costs are fairly well established by practice, precedent, and policy. However, trades can ounder if
parties are compelled to bear onerous agency transaction costs. The barrier to robust WQT is created when the trans-
action costs are high relative to the value created by trading. High transaction costs are caused by (1) unprecedented
circumstances or inexperienced programs, (2) complex trades, (3) large agency commitments, (4) inefficient BMPs, and
(5) overly conservative safety factors. The latter is often a problem, whereby multiple conservative assumptions together
require the number of PS credits purchased per those needed to be cost-prohibitive.
It is possible to significantly reduce many transaction costs by using dynamic system modeling (rather than static system
modeling) to analyze natural system behavior in the face of discharge alternatives. In a large market, with multiple po-
tential buyers and sellers, the long-term benefits would justify the fact that developing the model incurs costs up front.
4.4.2.4 Undefined Property Rights
The discharge volume is considered a property right that requires quantification and ownership, thus challenging suc-
cessful WQT. In a free market, property rights belong to the buyer and sellers. Whoever drives the market, i.e., sellers
or buyers, assigns the limited property rights of the transaction. The other extreme is where the regulator assumes
property rights. In a seller's market, the regulating agency, representing the demand side, assumes the property rights
of the discharge from the NPS. As such, the NPS transfers liability and control of the BMPs to the agency. On the other
hand, in a buyer's market, the regulating agency, representing the supply side, owns the property rights of the discharge.
It may transfer a limited set of these rights, including the liabilities associated with those rights, to a PS buyer through
a discharge permit, while still retaining control of the BMPs (Collentine, 2003). Without a clear definition of liability and
control of the property rights, stakeholders cannot weigh the true risks and returns of the potential trade.
4.5 Potential Solutions
The gaps and challenges to WQT complicate value- and risk-based decision making, leading to default decisions to
not trade. Current decisions to commit to WQT and negotiate the terms of WQT deals are based on partial informa-
tion that emphasizes known or predictable management, implementation, and transaction costs. The contributions of
assets created, liabilities reduced, risks and opportunities incurred or avoided, risks transferred at cost, public and pri-
vate economic valuation, and simplifications that compound uncertainty combine to restrain trading. These challenges
need to be addressed to enable WQT to thrive. Each of the following objectives and tools could be used alone or in
conjunction with another to gain insight into the utility of WQT and to streamline its application. Performing a thorough
economic valuation or System Dynamics Analysis (SDA) analysis for a program would help other programs to do the
same because they would not need to start from scratch.
4.5.1 Regulatory Efficiency
Inefficient regulatory practices increase the cost to develop and operate WQT exchanges. Reducing the regulatory
cost (and risk) of WQT exchange operations and trading would lower the administrative factor in credit price, thereby
improving the traders'DCFROI. Examples of such measures could involve special training for agencies, dedicated WQT
agency staff, clarification of legal issues that reduce disputes, improved system modeling, and simplified data manage-
ment. Free WQT markets minimize regulatory involvement, such that the regulatory agency sets the minimum rules of
engagement and then let the market propel itself.
These improvements could greatly increase the rate of WQT, which could further reduce the carrying cost of exchange
administration while accelerating the environmental benefits of reduced nutrient discharges.
17 Trade risk in this context does not involve financial risks to buyers or sellers, but rather the likelihood that the trades will not
result in gains in environmental functions and values equal to losses. A recent review of wetland mitigation trading in the United
States, for example, concludes that the inherent riskiness of wetland mitigation trades and trade terms that do not assign li-
ability to trading partners have resulted in a significant loss in wetland functions and values, and, possibly, a net loss in wetland
acres. See National Research Council, Committee on Mitigating Wetland Losses, Compensating for Wetland Losses
Under the Clean Water Act (2001) (quoted verbatim from Kuch and King, 2003).
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Measures to improve efficiency are both technically and economically feasible. The only caveat to the economic fea-
sibility is finding the agency budget to invest in improving staff, policies, practices, and equipment. Financing these
improvements by increasing the administrative cost of WQT could help fund this effort, but could be counterproductive
to stimulating trading.
4.5.2 PS Liability
The command-control compliance liability for PS dischargers is a significant potential driver for trading. As PS com-
mand-control liability rises, the value of satisfying the requirements would rise and the MPP for buyers would increase.
Stricter water quality objectives would improve the overall quality of the receiving waters, allowing agencies to decrease
the "safety factors" built into credit prices, which in turn would stimulate the generation and trading of water quality.
All things remaining unchanged, stricter PS discharge limits should increase the economic attractiveness of WQT,
encouraging more trades and better environmental protection. For Rahr, very strict restrictions against any additional
discharges into the Minnesota River Basin left the company no practicable alternative to engaging in WQT.
It would be technically and economically simple to stimulate WQT by shifting PS liability through a change in relevant
regulations. Politically, however, that change is daunting. If regulations were to occur, the economic impacts of such
changes would warrant extremely close inspection and justification before implementation. With current regulations,
PSs typically retain liability to meet permit limits, while NPSs take on the contractual obligations of the trade. In some
cases, however, liability transfers to a third party, such as for the cases in NC where the State assumed liability for a
failed BMP and the NPS would have to return subsidies.
4.5.3 Market Economic Valuation
Thorough valuations that are critical for informed decision-making may facilitate participants to engage in WQT. Ecosys-
tems supply stock and ow resources that are resources for productivity and growth, thereby generating societal value
or benefit. Establishing values for these resources is important to policymakers who are challenged to use regulations,
laws, and incentives to responsibly manage publicly owned natural resources, habitat, and species. The total economic
value of an ecosystem is the amount of money that all people who benefit from the watershed would be willing to pay
to see it protected (Whitehead, 1992). This total economic value is the amount society would be willing to pay for the
services and attributes of the ecosystem if they were not provided free of charge. This value comprises: (1) market eco-
nomic value, which is established by transactional precedent, and (2) non-market economic value, which is estimated
by methods that rely on public opinion surveys or costs of alternate strategies incurred without the resource.
Society values watersheds and wetlands because their existence and outputs (goods and services) are sources of current
and future consumptive and non-consumptive uses. For example, consumptive uses of wetlands include conversion to
cropland, and consumptive uses of wetland outputs include the harvesting offish from wetland fisheries. Non-consump-
tive benefits are long-lived, such as aesthetics or ood control. Values are multi-dimensional, and measured from several
perspectives: (1) individual owner, (2) individual user, (3) regional, and (4) societal (Leitch and Frigden, 2000). Overall,
market values are lower than non-market values for watersheds and wetlands (Stedman and Hanson, 2005).
Market values are economic values established and directly observable in functional markets, where landowners and
investors realize economic benefits. Since few markets exist for wetlands or watersheds, typical valuations focus on
the goods and services within those natural systems, such as harvested plants or animals, rather than the systems
themselves.
Components of ecosystems are potentially marketable, and suitable to market economic valuation. For example, ecosys-
tem health will in uence the rate of tree growth, the rate of commercial tree harvesting, and the net economic (market)
value of timber produced. Fisheries and commercial fishing provide an analogous source of economic value. However,
it is more difficult to quantify this value because fish are migratory, and their growth rate and net economic value as a
commodity are in uenced by the conditions of multiple, complex aquatic ecosystems.
Importantly, the total economic value of an ecosystem or hydrologic system is expressed in terms of the cost to keep
the land in its current use. The opportunity cost of alternate land use, such as draining a wetland and using it for crop-
land, is not considered.
Public policy makers face strategic decisions that affect the short-term and long-term health and productivity of natural
resource systems, including watersheds and wetlands. Strategic alternatives are always available for managing such
systems. Economic valuation provides a consistent metric for comparing the performance of strategic alternatives over
time, and justifying and communicating decision choices to stakeholders.
Several design criteria required for a quality market economic valuation, such as: (1) a clear definition of the system
(e.g., named wetland) or system component (e.g., annual shrimp production, in pounds) to be valued, (2) a clear de-
termination of the valuing party (municipal tax authority, commercial fisherman, regional grocery stores), (3) the years
to be used in establishing value, and (4) the regional market to be used in establishing value.
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The cost of establishing the market economic value of a natural system (or a zone within a system) is directly pro-
portional to the complexity of the system and its components, the diversity of the valuing population, and the volatility
of defining markets. The methods for establishing the market value of a watershed or a wetland are well established
and not controversial. However, difficulties exist in the interpretation, including: (1) communication challenges among
scientific disciplines, (2) economic principles not followed, (3) site-specific nature and variability, (4) unclear context
of valuation (why and how needed), and (5) shortage of scientific and economic information, leading to assumptions
(Leitch and Frigden, 2000). These challenges are readily overcome provided adequate time is available for the analysis
and sufficient resources are invested.
4.5.4 Non-market Economic Valuation
Watersheds and wetlands generate marketable and non-marketable natural goods and services, in economic terms.
Examples of non-marketable economic values include water quality control, stream ow control (and habitat manage-
ment. These non-marketable economic values primarily benefit the public. Unfortunately, because they are difficult to
quantify, non-market economic values often weigh less than market economic values in determining policy and natural
resource management strategy. However, including these values in economic assessments of strategy or policy should
encourage trading.
The ideal method for non-market valuation depends on the purpose or application of the valuation and the quality of
available information, and no single method applies to all situations. Non-market economic valuation methods are site-
specific, focusing on the physical properties, location, and the socio-economic context of the condition to be valued.
Wetlands, watersheds, and other natural systems perform multiple geologic, biologic, and hydrologic functions that
produce goods or support ecological services and socially valued outcomes. These functions, goods, services, and
outcomes are intricately intertwined, or bio-economically linked. For example, valuing the non-market benefit (e.g.,
downstream water quality and fish habitat) of investing in management controls (e.g., nutrient source reduction or wet-
land restoration) is difficult because the bio-economic linkage between cause and effect is indirect and complicated by
multiple physical and biological functions. Non-market (e.g., fish habitat) and market (e.g., commercial fishing revenue,
employment and tax revenue) goods and services are also linked, adding to the complexity of valuing strategies that
impact natural systems such as wetlands.
As an example, estuaries and their wetlands evenly distribute stream ow and runoff energy ( ood control) and loadings
(water quality), thereby generating market economic value in the fishing industry. The National Oceanic and Atmospheric
Administration (NOAA) reports that marine fisheries contributed $19.8 billion to the United States gross national product
in 1993. The business employed more than 364,000 fishers and onshore workers in 1991. Freshwater and saltwater
recreational fisheries in 1991 supported 924,600 jobs, contributing $1.1 billion in state sales tax, $227 million in state
income tax, and $2.1 billion in federal income tax. At a local level, it is possible to roughly approximate the minimum
non-market value of an estuary wetland loss as the replacement cost of lost local fishing revenue, including tax, employ-
ment, and other economic considerations.
Non-market economic valuation techniques are established, and widely used in the valuation of strategy and policy. They
are essential in the valuation of natural resource strategy, regulations, and policy, because the non-market component
of natural resources economic value typically outweighs the market component of economic value.18
In many situations, it is difficult to complete a non-market economic valuation rapidly enough and with enough sensi-
tivity to usefully inform cost/benefit decision makers. However, the techniques are appropriate when environmentally
sensitive, large-scale (e.g., watershed), or long-term and/or policy decisions are at stake. Overall, non-market economic
valuation should focus on what is indicated or learned by the valuation process, i.e., effective interpretation of results,
rather than the numeric results themselves.
4.5.5 Economic Investment Decision Methods
Economic investment decision methods comprise the classic DCFROI calculations used to evaluate competing capital
investment opportunities (Stermole and Stermole, 1993). These analyses quantify DCFROI, cash ow, and break-even
metrics. These methods map the expected performance of an investment in a cash ow format. Spreadsheets are often
used as the platform for these calculations. Cell data are entered as known, assumed, or expected (probabilistic) values
18 In their review and synthesis of the economic value of open space, Faushold and Lilieholm (1996) note, de Groot (1994) has
suggested a system for valuing natural systems based on a checklist of 37 functions, grouped into four categories: regulation
functions (ecological processes and life-support systems that supply and protect the quality of air, water and soil); carrier func-
tions (providing space and substrate for habitat, recreation, and cultivation); production functions (producing food, fiber, energy
and genetic material); and information functions (providing opportunities for reflection, spiritual enrichment, and cognitive
development).
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for revenues, costs, assets, and liabilities. Cash ow is discounted at a rate set by the analyst. Decision makers select
strategy based on the net present value of cash ow or return on investment.
This method is used ubiquitously in business and is taught as a core course in business schools as a way to compare
the economic value of strategic alternatives, including "no change." This methodology gives decision makers confidence
in the merit of their decisions, accelerating commitment of capital, leveraging negotiations, and structuring exit strate-
gies. Using this can accelerate the approval and implementation processes for each project, benefiting the environment
as a result.
Economic decision methods are completely feasible as they are already applied broadly to assess and select envi-
ronmental and other business strategies. Any costs would be borne by the trader. The cost to complete such analyses
depends on the complexity of the trading situation.
4.5.6 Probabilistic Analysis
Probabilistic analyses define uncertainty of known possible outcomes in terms of "probability of occurrence" and "mag-
nitude of occurrence." Calculations that are based on probabilistic inputs or data are more accurate than single-point
estimate inputs, which are subject to error and bias. Inputs for calculations are derived from experts in appropriate
fields of inquiry, such as the cost to treat water or the cost to dredge sediment from a specific location. Experts provide
inputs as guesses, estimates, range values, probable values, or other methods. Risk and opportunity are accounted for
in probable values, making them more reliable than the alternative inputs. Probabilistic inputs can be used for all, part,
or none of the uncertainties in a value calculation.
Probabilistic analysis is applicable to many kinds of problems, and is well established in practice and literature. This
approach may be widely employed at present, but reports of its use for WQT are not published. The cost of probabilistic
analysis of WQT strategy is higher than the cost of an assumption-based analysis. No agency cost would be required,
except when agency staff serve as experts providing information for analyses. This approach would provide decision
makers with more confidence in committing capital to WQT, thereby accelerating the rate at which all parties may agree
to the transaction terms. This approach is technically and economically feasible, providing a better understanding of the
data and uncertainties surrounding the data to improve the decision-making process.
4.5.7 System Dynamic Analysis
SDA is a modeling process that enables decision makers to evaluate the outcomes of their decisions by modeling in
advance of making investments. This process evaluates the consequences and sequencing of complex events and
phenomena inherent in many systems. Multiple strategies are always available to the investor or decision-maker. SDA
is capable of evaluating how systems will behave as a result of change, whether it is due to decided actions or uncon-
trolled events.
The WQT market and watersheds, like all complex systems, are networks of positive and negative feedback loops.
Complex interactions lead to possible unintended consequences and counter-intuitive behavior. SDA addresses these
characteristics inherent in the real world, simultaneously managing continuous and discontinuous relationships. Model
development and analyses proceed iteratively, refining the model with increasing knowledge of the system. Further-
more, SDA supports sensitivity analyses, either Monte Carlo or ad hoc, for the communication and defense of choices
to stakeholders. The different drivers, goals, and risk attitudes of buyers, sellers, and regulators necessitate quality
forecasts of information in order to commit capital to good use. Intuition and experience are not adequate when the
problem is too complicated and dynamic. The SDA structure is capable of resolving many of the challenges hindering
WQT. To adequately and cost-effectively ensure equivalence, SDA analyses may elucidate the complex processes af-
fecting equivalence and trading effectiveness. This tool has benefited many similar projects, including planning water
resources. Unfortunately, there are no available precedents for using this tool for WQT improvements.
4.6 Conclusions and Recommendations
To date, there is little direct evidence that WQT creates the advantages ascribed to it. However, specific trades have
demonstrated its utility, which lends to optimism that it may still be a compelling alternative to achieve water quality.
Many changes could be implemented to grow the WQT markets and encourage trades within the existing policies and
regulatory framework. For example, trading ratios could be distributed to include third-party beneficiaries (e.g., public
stakeholders), credits earned by implementing BMPs could be increased, or agencies could absorb specific transaction
costs currently paid by traders. Indeed, a number of options could facilitate this growth to the extent they address the
identified challenges.
Economic considerations must support WQT for it to be a viable tool to achieve water quality standards. The market
should acknowledge the true valuation of an exchange. Currently, several information gaps typically elicit ineffective valu-
ation that does not accurately address risks and returns, thereby generating economic trading challenges. Establishing
sophisticated methods of decision-making and of evaluating and managing risk would promote WQT's viability. Without
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complete valuations of the WQT alternative, which comprehensively address the information gaps and challenges, the
market may not achieve its optimum potential. In fact, it may lose its marketability entirely. To clarify, every trade does
not mandate a rigorous valuation process. Rather, the market viability would benefit from a framework within which to
more readily qualify costs and benefits of WQT and specific designs. These valuations will enable decision makers and
policy makers to quantify the value of investing in WQT as a discharge management strategy of choice.
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5.0 Trading Regulations Literature Review
The Federal Water Pollution Control Act, or CWA, of 1972 provides the foundation for WQT in that it establishes regu-
lations to protect water quality and allows exibility with respect to how those requirements can be met. This national
law was enacted to restore and maintain the chemical, physical, and biological integrity of the nation's waters. The act
established national policy and preserved the primary responsibilities and rights of the states to prevent, reduce, and
eliminate nutrient discharges. In order to carry out this policy, USEPA was given the authority to require permits of PSs
that discharge nutrients into waters of the United States, through the NPDES permit program (CWA Sections 402 and
404). PSs are discrete conveyances, such as pipes or man-made ditches (40 CFR 122.2). These permits set ef uent
quality limitations and require implementation of best available technologies that may include specific BMPs. USEPA
allowed the states to decide how NPSs should be regulated (IDEQ, 2005c).
Amendments to CWA (Section 319) in 1987 included the requirements for states to develop and implement programs to
control NPSs of nutrient discharges. Section 319 does not provide direct authority to regulate NPSs of nutrient discharges
(Heimlich, 2003), but it does establish mechanisms for states, tribes, and territories to receive support for programs de-
veloped to control NPSs of nutrients in the form of technical and financial assistance, training, technology transfer, and
monitoring to assess the success of projects to control NPSs of nutrients (USEPA, 2005b). Programs developed by the
states to control NPSs of nutrients have tended to emphasize voluntary actions (Heimlich, 2003). According to Heimlich
(2003), 31 states have taken additional steps towards controlling NPSs of nutrients by passing laws or implementing
programs that include enforceable mechanisms to protect water quality from agricultural sources of nutrients. These
enforceable mechanisms tend to emphasize technology standards. The Tar-Pamlico and Neuse River Basin NSW Strate-
gies in North Carolina provide two examples of state rules that emphasize technology standards to address agricultural
and urban NPSs of nutrients by requiring that these sources achieve nutrient discharge requirements by implementing
their choice of BMPs from a pre-approved list for which the state had determined average nutrient removal efficiencies
(see Section 9.0 for more information).
The NPDES program has made significant progress in reducing pollutants discharged by PSs to the nation's waters
(USEPA, 2003b); however, between 40 and 50 percent of the streams, rivers, and lakes still remain below water quality
standards. Advocacy groups blame the USEPA for waters still being impaired due to the delays in issuing guidance and
providing assistance, states for not reaching beyond conventional knowledge and approaches, and the US Congress
for not providing adequate resources to meet USEPA and state needs. More than 40 lawsuits, in 38 states, have been
filed against USEPA and states for failure to fulfill requirements of the CWA. Consequently, innovative approaches are
being sought to further recover water quality. WQT is one such approach that promises greater efficiency in achieving
water quality goals on a watershed basis (USEPA, 2003a). WQT projects have occurred in the United States since the
early 1980s (Copeland, 2005).
The CWA also requires the development of water quality standards for all contaminants in surface waters, which in-
clude standards for designated uses, water quality criteria, and antidegradation provisions (Section 303[c]). The act
also requires the establishment of TMDLs (Section 303[d][1]). TMDLs are the amount of an identified pollutant that a
specific stream, lake, river, or other water body can "accommodate" without violating state water quality standards and
an allocation of that amount to the pollutant's sources (USEPA, 2003c). States are required by CWA to address both
PSs and NPSs by establishing TMDLs for waters that do not meet water quality goals. These TMDLs typically function
to set the baseline for determining trading units called credits. TMDLs must be approved by USEPA and developed
for every pollutant that causes a watershed to exceed clean water limits; thus, TMDLs are generated specifically for
nutrients such as nitrogen and phosphorus.
In addition to the CWA, the Coastal Zone Management Act Reauthorization Amendments (CZARA) of 1990 contains
NPS water nutrient requirements. The CZARA requires that states with approved coastal zone programs submit plans
to implement measures for NPSs of nutrients to restore and protect coastal waters. States can employ voluntary mea-
sures, such as education, technical assistance, and financial assistance, but must be able to enforce these measures
should voluntary approaches fail (Heimlich, 2003).
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Arguably, one factor that seems to have hampered the ability of USEPA and states to protect water quality and ensure
that state water quality standards are not violated is the challenge of developing programs (regulatory or voluntary) to
control NPSs of nutrients. As discussed in Section 1.0, NPSs, particularly agriculture, are important sources of water
nutrients. It is difficult to measure the contribution of an individual NPS of nutrients or the actual effectiveness of vari-
ous BMPs to control discharges because of the diffuse nature of this type of discharge, as discussed in Section 3.0.
WQT programs are yet another mechanism that may increase the participation of NPSs in implementation of BMPs
to improve water quality by providing another platform for education and means by which land owners receive outside
funds to make improvements to their properties (by implementing BMPs).
5.1 USEPA Water Quality Trading Policy
To encourage the implementation of WQT programs, USEPA developed a WQT policy in 2003 (USEPA, 2003a). This
policy provides guidance for states, interstate agencies, and tribes to assist them in developing and implementing such
programs. Specifically, the policy is intended to encourage voluntary trading programs that facilitate implementation
of TMDLs, reduce the costs of compliance with CWA regulations, establish incentives for voluntary reductions, and
promote watershed-based initiatives. Voluntary trading before TMDLs are established could decrease the pollutant
reduction required by the TMDL and possibly improve water quality enough to meet water quality goals and eliminate
the need for a TMDL.
Within the trading approach, ecological benefits that complement water quality improvements are promoted by the
policy. For example, two of the trading objectives of USEPA's trading policy discuss the use of wetlands in trades, and
are stated as follows:
F. Achieves greater environmental benefits than those under existing regulatory programs. EPA supports the
creation of water quality trading credits in ways that achieve ancillary environmental benefits beyond the required
reductions in specific nutrient loads, such as the creation and restoration of wetlands, floodplains and wildlife
and/or waterfowl habitat.
H. Combines ecological services to achieve multiple environmental and economic benefits, such as wetland
restoration or the implementation of management practices that improve water quality and habitat.
Trading is particularly encouraged by the policy for nutrient (e.g., phosphorus and nitrogen) and sediment loads. Other
pollutants may pose a higher level of risk and should receive a higher level of scrutiny to ensure that they are consistent
with water quality standards. The geographic area for trading programs is described by the policy as the watershed or
area covered by an approved TMDL. Trading credits are defined by the policy as nutrient reductions greater than those
required by a regulatory requirement or established under a TMDL. USEPA encourages the inclusion of specific trad-
ing provisions in the TMDL itself, in NPDES permits, in watershed plans, and the continuing planning process (USEPA,
2003a).
USEPA's water quality policy identifies several mechanisms for providing provisions for trading, including legislation,
rule making, incorporating provisions for trading into NPDES permits, and establishing provisions for trading in TMDLs
or watershed plans. As discussed in the case studies presented in Section 6.0 through 9.0, NPDES permits have pro-
vided an essential part of the regulatory basis for WQT programs, and TMDLs have furnished the driver for trading.
For example, the NPDES permit issued to Rahr (Section 7.0), stringently capped the company's oxygen-demanding
discharge into the Minnesota River Basin. The cap was set according to the TMDL, which allocated 53,400 pounds per
day of CBOD at mile 25 and downstream of Rahr.
North Carolina took a slightly different approach to using NPDES permits in WQT programs. Both the Tar-Pamlico and
Neuse River Basin WQT programs (Section 9.0) tailored the NPDES permits of PSs within the river basin to provide them
with exibility in meeting permit requirements, which furnished the option of trading. Both programs establish associa-
tions that include a majority of the PS dischargers within the basin. The NPDES permits of the Association members
do not contain limits for TN and TP, which means that if they overperform, they are not subject to the antibacksliding
requirements in the federal CWA (these requirements would result in adjustments in permit limits if association members
showed they could meet more stringent requirements). The NPDES permits do, however, contain a "reopener" clause
stating that if conditions in the agreement signed by the Association, the North Carolina Environmental Management
Commission (NCEMC), the North Carolina Division of Water Quality (NCDWQ), and the Department of Soil and Water
are violated, then permits would be revised to impose new discharge limits (Kerr etal., 2000). The agreement specifies
a group discharge allowance forTN and TP. As with Tar-Pamlico, the NPDES permits of individual dischargers within
the NRCA do not contain a discharge limit forTN. Instead, the TN limit for the NRCA is specified in the group compli-
ance NPDES Permit (USEPA, 2002b). Both of these programs were established prior to development of TMDLs for
the river basin, but the final TMDLs agreed with the limits that had already been established by these programs. These
programs allow for trading among PSs and trading with NPSs via a state-administered fund for every pound by which
the aggregate annual discharge of the association exceeds the established limit.
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The Water Quality Trading Policy also identifies several key elements that should be incorporated into trading programs
so that they are credible and successful. Units of trade (e.g., nutrient-specific credits) are necessary for trading to oc-
cur. These may be expressed in rates or mass per unit time. Credits should be generated before or during the same
period they are used to comply with a monthly, seasonal, or annual limitation or requirement specified in an NPDES
permit. As long as the discharge controls or management practices are functioning to reduce nutrients that generate
credits, credits may be generated (USEPA, 2003a). To encourage trading, there needs to be clear authority to trade and
clear legal protection for using the rights purchased (in the form of water quality credits) to meet established regulatory
requirements (Kieser and Fang, 2005).
Specific requirements for trading programs will vary based on the location and circumstances of the trading. These re-
quirements are left up to the states to generate, although USEPA's trading policy encourages consultation with USEPA
during program development. USEPA believes trading programs must have clear and consistent standards for measuring
compliance and to ensure that appropriate enforcement action can be taken for noncompliance. The incorporation of
compliance and enforcement provisions within a trading program framework is an essential element for a credible trad-
ing program, according to USEPA's water quality policy (USEPA, 2003a). These may include a combination of record
keeping, monitoring, reporting, and inspections.
Enforcement provisions within the trading program must ensure legal accountability for generation of credits that are
traded. Compliance audits should be conducted frequently enough to ensure that a high level of compliance is maintained
across the program. If compliance is not maintained, the NPDES permit holder using those credits would be respon-
sible for complying with discharge limitations as if the trade had not occurred. For example, in the Cherry Creek WQT
program in Colorado (Section 6.0) and the LBR WQT program in Idaho (Section 8.0), the PS project owner that initiated
the trade is responsible for ensuring BMPs selected to generate credits are properly implemented and for any ensuing
liability issues. The Idaho program also requires the BMP implemented to be certified as installed before the phosphorus
credit can be generated and traded. In the Rahrtrading program, the NPDES permit ensured legal enforceability of the
selected controls by prescribing the types of BMPs, selection process, reporting, and goals. MPCA was charged with
verifying each trade and confirming annual nutrient reductions prescribed in the permit (Breetz et a/., 2004).
On the subject of liability, Raffini and Robertson (2005) noted that wetland mitigation banking has dealt with liability dif-
ferently than WQT in order to ensure that the service offered by wetland mitigation banking is attractive to developers
and dischargers. The transfer of liability from the credit purchaser to the third-party mitigator was identified as critical
to making wetland mitigation banking work: credit purchasers are not interested in buying healthy wetlands or clean
water; they are purchasing rapid permitting and avoidance of liability if a mitigation site fails. In the case of Cherry Creek
and Rahr, the credit purchaser is not offered a release from liability if the mitigation is ineffective and may be faced by
the need to continuously monitor and maintain the mitigation measures, incurring additional costs and being exposed
to ongoing uncertainty. The LBR also places liability on the credit purchaser to ensure that the BMPs are performing.
This makes the purchase of credits much less attractive to PSs. Transfer of legal and financial liability from the credit
purchaser to another entity is one way of making nutrient credits a more desirable commodity (Raffini and Robertson,
2005). North Carolina handled the issue of liability in the Tar-Pamlico and Neuse River Basins by assigning identification
and management of WQT mitigation projects to existing government entities which are responsible for ensuring NPS
credits are generated. However, PS compliance associations have not needed to purchase nutrient credits to date.
Another form of program auditing included in the USEPA water quality policy is providing program transparency to
the public. Public participation and comments on trading program development, use, and evaluation should be sought
to ensure that water quality objectives and economic efficiencies are achieved, and that trading does not result in an
impairment of designated uses (USEPA, 2003a).
Some states have passed water quality laws, rules, regulations, and/or policies supporting and regulating watershed-
specific trading operations. As discussed in the case studies, Colorado, Idaho, and North Carolina developed regulations
to support and govern WQT. In the case of the LBR, no trading has occurred to date because the phosphorus TMDL
has not been finalized; as a result, the trigger for trading is missing. New trading programs would also need to develop
similar watershed-specific policies, rules or regulations. These provide the drivers and trading framework necessary for
watersheds to implement exible programs to accommodate local conditions and socioeconomic factors (Kieser and
Fang, no date). Regional or state trading policies exist for 10 states. There are several different models for managing
trades, including:
• State-managed exchange - state is broker (CT)
• NPDES Compliance Association - association is the broker (NC Neuse and Tar-Pamlico)
• Third party is broker, such as a non-profit, private enterprise, conservation organization, or district, etc. (Idaho;
South Nation, Ontario)
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Credit managers can facilitate trading by assisting numerous credit buyers and sellers in finding each other. Further-
more, they can identify and facilitate trades among multiple buyers and potential sellers. Multiple locations with small
amounts of credit could be consolidated by an administering organization for sale to a large buyer. Other functions of
credit managers or brokers could perform include: verifying and discounting credits that vary widely in performance
and uncertainty, optimizing the selection and location of BMPs, and providing escrow or backup credits in case of BMP
failure (Hough and Hall, 2005).
5.2 Agricultural Policy Drivers for Using Wetlands in WQT
For decades, the USDA has encouraged conservation measures on farmland. Towards that goal, several "Farm Bills"
have established agricultural policy to increasingly rely on financial incentives to promote conservation practices. Many
of the provisions of the farm bills encourage the use of wetlands to achieve environmental quality.
• The 1985 Farm Bill created the Conservation Reserve Program, which included a provision to link eligibility for
financial incentives to wetland conservation practiced on ecologically sensitive land.
• The 1990 Farm Bill created the Wetlands Reserve Program, a federal program to restore and place conservation
easements on wetlands, and authorized the Water Quality Incentives Program.
• The 1996 Farm Bill consolidated several programs created in previous Farm Bills into the Environmental Quality
Incentives Program. Among other functions, the Environmental Quality Incentives Program funds BMPs on working
farmland.
• The 2002 Farm Bill dramatically increased funding for CS, making it possible to restore much of the country's lost
or damaged wetlands.
The USDA has been promoting the applications of private-sector markets for achieving environmental goods and services
(USDA, 2005). While traditional financial incentives have been through cost-share programs, trading in environmental
credits will provide the next generation of incentives for conservation. In large measure, the World Trade Organization
has driven this potential expansion of using environmental markets by disputing trades associated with agricultural
production subsidies. Specific restrictions limit the amount of financial support the farm may receive without losing their
eligibility to be considered "green box", a status that exempts them from annual limits on support. Alternatively, WQT
markets would allow agricultural operations to earn income by providing nutrient credits to those that need them. In fact,
Congress will vote on a proposed 2007 Farm Bill that would allow credits generated by BMPs implemented with federal
funds to be sold within the market (USDA, 2006). Support by Congress of this measure would significantly promote the
participation of agricultural NPSs in WQT.
5.3 Regulations Related to Wetlands and Trading Programs
The CWA contains requirement that could have implications for wetlands constructed as a part of a WQT program.
Waste treatment systems designed to satisfy the requirements of the CWA are by definition not considered waters of
the United States (USERA, 2000a). However, if a constructed wetland is constructed in a water of the United States,
the area will remain a water of the United States unless a CWA Section 404 permit is obtained that identifies it as an
excluded waste treatment system. It is possible that the constructed wetland will revert to a water of the United States
if it is abandoned or is no longer being used as a treatment system and it fits the definition of a water of the United
States. This definition is met if the constructed wetland has wetland characteristics (hydrology, soils, vegetation), is an
interstate wetland, is adjacent to another water of the United States, or is an isolated intrastate water that has con-
nections to interstate commerce (USERA, 2000a). These requirements have regulatory implications. If a constructed
wetland is built to generate credits for a WQT program and the credits are assigned a finite duration, then the wetland
could become regulated under the CWA, thereby limiting potential uses of the land. This could serve as a deterrent
to using constructed wetlands as a BMP in WQT programs. If USEPA and states would like to encourage the use of
constructed wetlands in WQT programs, then the long-term regulatory implications of building constructed wetlands to
generate credits for WQT programs will need to be modified.
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6.0 Case Study - Cherry Creek, Colorado
6.1 Overview
The Cherry Creek Basin trading program aims to protect water quality in the basin through trades between two PSs
and between PSs and NPSs. Several tributaries and the Cherry Creek mainstem ow into the 850-acre Cherry Creek
Reservoir, located in southeast Denver, Colorado (Figure 6-1) (CCBWQA, 2005). The U.S. Army Corps of Engineers
(USAGE) constructed the dam establishing the Cherry Creek Reservoir in 1950 to protect Denver from coding (USAGE,
undated). The USAGE owns the Cherry Creek Reservoir and the 3,915 acres of land surrounding it, but leases both to
the State of Colorado. That land is now the Cherry Creek State Recreation Area. Cherry Creek ows from the reservoir
supplying a watershed of 245,500 acres for Denver. Groundwater also ows into Cherry Creek from beneath the dam
downstream of the reservoir, supplementing the watershed supply (CCBWQA, 2003a).The CCBWQA administers and
manages the water quality issues of this watershed. Within the watershed, six WTFs discharge ef uent as PSs into the
streams owing into the Cherry Creek Reservoir. Trading between PSs occurred as early as 1985, expanding to allow
trades with NPSs in 1989. Final guidance for trades was approved in 1997. Since then, three trades have occurred, one
of which involved an NPS (Breetz et a/., 2004).
Legend
Stream
Stream Intermittent
Lake
Interstate
Highway
Watershed Boundary
FIGURE 6-1
The Cherry Creek Basin
Figure 6-1 The Cherry Creek Basin (CCBWQA, 2005).
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6.2 Background
The State of Colorado initiated WQT in 1989 through the state's Department of Public Health and Environment when
its Water Quality Control Commission embraced the Cherry Creek Reservoir Control Regulation, listed as Regulation
#72. The regulation approved WQT between PS and NPS discharges of phosphorus. Four years earlier, the Water
Quality Control Commission distributed TMDL allocations of phosphorus aimed to control eutrophication of the Cherry
Creek Reservoir to the PSs with discharges into the reservoir. PS dischargers had to obtain a permit under NPDES
before discharging ef uent into the streams owing into the Cherry Creek Reservoir. The Department of Public Health
and Environment accepted trades with NPSs despite the fact that these sources were unregulated. Their rationale was
that NPSs at that time represented approximately 80 percent of the phosphorus load into the basin. The state's impetus
for the trading program was to allow growth while preserving the aquatic ecosystem of the basin. Regulation #72 also
legally mandated the CCBWQAto administer the basin (Breetz et a/., 2004).
In 1997, approval of guidelines for Regulation #72 trading finally gave direction to the program. Guidance identified
trading opportunities, determination of trading ratios and credits, procedures for applicants, evaluation criteria, and trade
implementation. Revisions to Regulation #72 in 2001 established the TMAL allocating phosphorus loads into the basin
to both PSs and NPSs. In 2003, they issued the Cherry Creek Reservoir 2003 Watershed Plan with new guidelines to
re ectthe updated trading program. The plan set the surface water standard forTPat40 micrograms per liter (ug/L). The
Trading Program Guidelines offered more detail on trade evaluations and implementation. The TMAL was set at 14,270
pounds of phosphorus per year, of which the CCBWQA allocated approximately 72 percent (10,300 pounds per year
[Ib/yr]) to NPSs and regulated stormwater sources, 13 percent (1,900 Ib/yr) to municipal and industrial PSs, 8 percent
(1,150 Ib/yr) to background sources, and 3 percent (450 Ib/yr) to individual septic systems (CCBWQA, 2003a, 2003b, and
2003c). An additional 3 percent was allocated to reductions achieved by the Reserve Pool and Phosphorus Bank.
The CCBWQA set up these two entities (Reserve Pool and Phosphorus Bank), each initially worth up to 216 pounds of
phosphorus per year to broker trades. The Phosphorus Bank obtained its 216 pounds of phosphorus per year through
four projects the CCBWQA initiated in the early 1990s and has been maintaining since then. The Reserve Pool could earn
its 216 pounds of phosphorus per year through new NPS control projects. A PS discharger could apply for Reserve Pool
credits either for a BMP project or for extending their wastewater service to a semi-urban area. In total, PS dischargers
could buy or lease up to 432 pounds of phosphorus per year, i.e., the sum of the Reserve Pool and Phosphorus Bank, of
new or increased allocations, bringing their total allocation to 2,310 Ib/yr, or 16 percent of the TMAL. Semi-urban areas,
which are not designated to a service area but are planned for urbanization in the future, were allocated 236 credits,
already included in the PS allocation (CCBWQA, 2003a; CCBWQA, 2005).
Recent amendments to Regulation #72, effective as of December 30, 2004, removed the upper limit of 216 pounds
of phosphorus per year that the Reserve Pool could achieve. The NPSs and regulated stormwater sources were also
increased to 10,506 pounds of phosphorus per year to include the Phosphorus Bank's 216 pounds of phosphorus per
year (CCBWQA, 2005). These changes are intended to encourage more interest in trading by eliminating ceilings on
a trade's potential.
Stormwater is included in the trading program as another regulated discharge. Colorado regulates stormwater discharges
through a mandate for NPDES permitting. The permit adds requirements for stormwater BMPs to reduce phosphorus
discharges into surface waters (Breetz et a/., 2004).
6.3 Program Performance
The four criteria fundamental to a successful trading program involving NPSs include equivalency, additionality, ac-
countability, and efficiency (Fang and Easter, 2003). The first three criteria address technical and administrative issues,
necessary to evaluate efficiency. Equivalency, which is a measure of how nutrient loads from various sources relate to
the constituent of concern to be offset, is vital to avoid surpassing the TMDL. Conversion ratios accounted for temporal,
spatial, and/or chemical differences in the sources. Such differences are often complex, so this criterion is fraught with
uncertainties, which must also be factored into the trade. Additionality stipulates that any NPS offset that would have
occurred regardless of the trading program cannot count toward a trade. This prevents double counting by ensuring
that a nutrient control activity counts toward only one objective if multiple objectives are met. For example, phosphorus
reduction from a BMP that is already necessary for land development activities is not eligible for trading (Breetz et a/.,
2004). Finally, accountability mandates appropriate monitoring and oversight to ensure proper implementation of all
program requirements. Performance, design monitoring, and reporting could satisfy this criterion. Conservatively set-
ting the conversion and trading ratios also contributes to satisfying this criterion. The last criterion is one of economics.
Efficiency mandates the trade proceed only when one source is able to more cost-effectively reduce its discharges
than another source. This condition is critical to making the program financially attractive, and thus marketable (Fang
and Easter, 2003; Jaksch, 2000).
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The Cherry Creek trading program structure is conducive for success in achieving these four criteria. Conversion ratios
account for differences in particulate versus dissolved forms of phosphorus. In addition, trading ratios, which qualita-
tively account for spatial differences in loads, add a level of certainty to equivalency. Additionality precludes a credit
from counting towards a trade if it already existed or was required. Monitoring and reporting are essential components
of the program, providing accountability. A PS could increase its TMAL allocation through trading more cost-effectively
than through implementing its own controls.
However, as the following sections present, threats to these criteria, particularly to equivalency and efficiency, have
thus far hindered this success. Complexities involved in the determination of conversion and trading ratios hindered
the certainty of equivalency. However, this factor should be more quantitative, and account for temporal differences, as
well. In fact, equivalency must account for the effects of the dynamic interactions of processes, such as concentrations
of other nutrients. Establishing equivalency with more certainty must be achieved without burdening the program with
added costs. Financial incentives are critical to perpetuating the program, and are currently not sufficient to stimulate
trading. Currently, there is not enough need for most PSs to reduce their phosphorus loads.
6.4 Technical Performance
The trading program operates on a system where one credit is equivalent to 1 pound of phosphorus per year. Trading
credits functions through a clearinghouse structure, whereby the CCBWQA may sell credits to dischargers needing to
increase their allocation. A PS discharger may also trade directly with another PS discharger if the buyer at least strives
to minimize phosphorus loadings (Breetz et a/., 2004).
Success of the trading program is predicated on PSs abiding by their discharge limits. The CCBWQA mandates that, prior
to discharge, PSs must remove as much phosphorus as possible through advance treatment or secondary treatment
followed by land application. The 30-day average concentration of phosphorus in ef uent must not exceed 0.05 mg/L.
Dischargers using land application must achieve a 30-day average concentration of phosphorus less than 0.05 mg/L
divided by the return ow rate, unless lysimeters are used, in which case the ef uent concentration limit is 1.0 mg/L
(CCBWQA, 2005). Such restrictions aim to control the release of phosphorus in the solid phase into the watershed
through stormwater runoff.
The trading program incorporated safety factors to provide accountability. These factors aimed to account for project
uncertainties, particularly those in Pollution Reduction Facility (PRF) effectiveness and those associated with complex
dynamic fate and transport processes. The CCBWQA set equivalency at 2.9:1 forTP and 2.2:1 for dissolved phospho-
rus. These ratios were derived from a USEPA-approved method to assess the settling of suspended solids, ratios of
dissolved-to-total suspended solids (TSS) from a comparable facility, and a fate and transport adjustment (Breetz et
a/., 2004). These ratios indicate 2.9 credits of reduced TP discharge or 2.2 credits for dissolved phosphorus discharge
are needed for each pound of phosphorus discharged from a PS. Accordingly, Equation 6-1 calculates the number of
credits of phosphorus earned based on the weight of phosphorus reduced per year, using a conversion ratio.
, pounds_per yearp reduced (6-1)
credits earnedp=- =^-^—LE^I
p CR
where credits_earnedP = credits earned from trade, defined as pounds of phosphorus per year
pounds_per_yearp = Ib/yr of phosphorus reduced by BMPs
CR = conversion ratio
Credits that are earned from the BMP implementation are added to the allocation. With a minimum trading ratio of 2:1,
a minimum of twice the earned credits is lost from the entity trading its credits (Breetz et al., 2004).
(6-2)
credit_lostp=credits_earned«TR
where credit_lostp = credits lost from allocation
TR = trade ratio
Four "historic trade projects" supplied the Phosphorus Bank with its 216 credits. These PRFs include the Shop Creek
detention pond and wetlands established in 1990 (Figure 6-2), Quincy Drainage detention pond established in 1996,
Cottonwood Perimeter Road Pond established in 1996, and improvements to the East Shade Shelter streambank estab-
lished in 1996 (CCBWQA, 2005; Wulliman, undated). The CCBWQA is charged with maintaining and managing these
PRFs. If approved, a PS discharger may buy credits from the CCBWQA for a price set by the CCBWQA. For example,
a PS discharger needing an additional 20 credits, worth 58 credits with a 2.9:1 equivalence, could purchase twice that,
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i.e., 116 credits, from the CCBWQA's Phosphorus Bank, which is now part of the NPS and regulated stormwater al-
location. To date, no discharger has requested a withdrawal from the Phosphorus Bank (CCBWQA, 2005).
These historic PRFs earned their credits primarily through erosion and wetland restoration, and continue to reduce
phosphorus loads into the Cherry Creek Reservoir. The performance of each PRF is monitored annually by measur-
ing and comparing phosphorus loads upstream and downstream of each PRF. Development had significantly eroded
Shop Creek and eliminated all of its vegetation. The Shop Creek Water Quality Improvement Project created wetlands
to stabilize channel erosion and reduce phosphorus load to the Cherry Creek Reservoir. The project established a
9-acre-foot detention pond upstream of five wetland channels in series, each stepped down from the previous. Deten-
tion ponds typically fill with water during storm events and then allow for slow drainage thereafter, allowing time for the
particulates with phosphorus to settle. Each wetland channel adds settling time, as well as natural biological, chemical,
and physical treatment, and infiltration. Between 1990 and 2000, phosphorus leaving the Shop Creek wetlands to enter
the Cherry Creek Reservoir averaged 173 pounds less than that entering the detention pond, representing an aver-
age reduction of 63 percent. The Quincy Drainage detention pond reduced phosphorus loads by restoring a vegetated
infiltration basin. Measurements collected before and after this PRF from 1996 to 1999 calculated average load reduc-
tions of 138 pounds and efficiencies of 99 percent. The Cottonwood Creek Perimeter Road Pond PRF involved road
improvements to decrease water ow, restoring vegetation through the channel, thereby reducing phosphorus loadings.
In 2004, phosphorus measurements before (3,334 pounds) and after (2,592 pounds) the pond indicate an average an-
nual load reduction of 742 pounds, i.e., 22 percent (CCBWQA, 2005). Finally, the East Side Shade Shelters area had
suffered from severe erosion, which was remedied through gravel benching and vegetation along the shoreline. This
stabilization reduced phosphorus loadings into the Cherry Creek Reservoir. Although actual data on the performance of
this PRF is not readily available, the 2003 Watershed Plan reports an average of 15 Ib/yr. In total, annual measurements
of phosphorus loads before and after the PRFs indicate that they reduce on average over 1,100 pounds annually. With
equivalency and trading ratios considered, the reductions support the 216 credits for the Phosphorus Bank (Wulliman,
undated; CCBWQA, 2005; CCBWQA, 2003a).
Although trading with the Phosphorus Bank has yet to occur, three projects have created new credits that reside in the
Reserve Pool available for trade. New BMP projects or PRFs supply credits for the Reserve Pool to allow for growth and
expansion. The CCBWQA may purchase NPS phosphorus reductions for Reserve Pool credits. Any entity construct-
ing or planning a PRF may apply to the CCBWQA for credits anticipated with that PRF. If granted CCBWQA approval,
that entity may then buy those credits to offset its own discharge, sell them to another discharger, or retire them.19 No
longer capped at 216 credits, the Reserve Pool may achieve however many credits an innovative approach may offer.
The trading ratio for the latter must be at least 2:1, but should increase for PSs that are farther than the NPS is from
the Cherry Creek Reservoir. These ratios aim to assure equivalence. Until December 30, 2004, the trade ratio could
not exceed 3:1, but the amendments removed that upper limit (CCBWQA, 2005).
Of the three new credit trades, two were needed to satisfy significant growth to semi-urban areas since initial alloca-
tions. Specifically, in 2004, the Pinery Water and Sanitation District granted use of 25 of its credits to the Plum Creek
Wastewater CCBWQA, and 25 credits were taken from the semi-urban area allocation. Another 10 credits from the
semi-urban allocation went to the City of Aurora for Land Applications within the Cherry Creek Watershed (CCBWQA,
2005). The third trade was between PS and NPS, the first of its kind for the program. In 2004, the Arapahoe County
Water and Wastewater Authority (ACWWA) planned to modify one of its stormwater detention ponds, located 2 miles
upstream of its discharge point. In doing so, it would reduce 165 pounds of phosphorus to supplement its own TMAL
allocation. Trading ratios were critical to the amount of credits that the transaction was worth. According to the TP ratio
of 2.9:1, the reduction will earn ACWWA 57 credits. While ACWWA receives 57 credits, the minimum trade ratio of 2:1
reduces the NPS allocation by 114 credits, resulting in a reduction in the TMAL (CCBWQA, 2005).
Despite effective reductions, mass balances indicate approximately 4,000 pounds of phosphorus annually accumulate
in the Cherry Creek Reservoir (CCBWQA, 2003a). Accumulated phosphorus acts as an internal load for which the
TMAL allocations do not account.
The CCBWQA continues to pursue other PRFs intended to improve the water quality as much as possible. In 2002, the
CCBWQA contributed 16.5 percent of the funds needed for the Piney Creek Reclamation project, which was completed
in 2004. Soil erosion controls and restoration of riparian vegetation along 5,100 feet reduce approximately 90 pounds of
phosphorus annually from entering the Cherry Creek Reservoir. In 2002, another PRF involved a second detention pond
on Cottonwood Creek just outside the Park, west of Peoria Street, aimed to complement the Park Perimeter Road PRF.
By 2004, this PRF reduced phosphorus loads, measured at 2,590 pounds upstream and 1,499 pounds downstream of
the detention pond. The Cottonwood Reclamation project of 2003 aimed to reclaim the natural wetlands capabilities of
the area covering 11,600 feet along the stream. Annual phosphorus loadings are estimated to decrease by approximately
730 pounds through soil erosion control, wetlands treatment, infiltration, and settling.
19 When a credit is retired, it is no longer eligible for credit, but rather serves solely to improve the environment.
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The only available indication of a method to derive this estimate is comparisons with Shop Creek results and a 2004
study that indicated its feasibility. The CCBWQA has also been conducting feasibility studies to restore, reclaim, and
construct wetlands in the Cherry Creek State Park. An agreement drafted in 2004 identifies those responsible for any
PRFs within the park. When completed, 60 acres of wetlands will control approximately 600 pounds of phosphorus
per year. Again, a methodology to derive this estimate is not clear, but sampling and analyses in 2004 and testing of
wetlands reclamation on a smaller scale seem to have factored into this methodology (CCBWQA, 2005). Credits from
CCBWQA-funded projects, aside from those for the Phosphorus Bank, are not eligible for trading, but instead aim to
further improve water quality (Colorado Department of Public Health and Environment, Water Quality Control Commis-
sion, 2001).
Figure 62
Cherry Creek Basin
East Side Shelters
PRF
Quincy Drainage
PRF
Shop Creek
PRF
LEGEND:
O Sample Site
Road
^—^— Stream
(^^B Reservoir/Pondi'PRF
N
0 05 10 2.0 M
APPROX SCALE
Note Labeled site locations for Quincy Drainage and East Side Shelters PRFs are approximate.
Figure 6-2 Cherry Creek Basin with selected PRFs identified (CCBWQA, 2005).
6.5 Economic Performance
The CCBWQA is funded through a combination of property taxes, user fees and grants. The Base Price for credits
purchased from the Phosphorus Bank is based on the minimum cost the CCBWQA would incur to pursue additional
projects that would achieve comparable reductions (CCBWQA, 2003b). Applications to create Reserve Pool credits cost
$2,500, and a discharger must pay an additional $500 to cover costs incurred by the CCBWQA to evaluate the request
for credit withdrawal from the Phosphorus Bank. The cost of Reserve Pool credits depends on the BMP implemented
to achieve the offset. When the ACWWA retrofitted the detention pond, they achieved 57 credits. Therefore, with each
credit worth $8,000 (the unit cost for traditional controls), and a cost to retrofit the detention pond to achieve those
credits of $400,000, the gain in value was $56,000 (Breetz et al., 2004). Subtracting the cost of $2,500 to apply for
credits from the Reserve Pool, the net value for just 57 credits is $53,500. Considering the avoidance of the alternative
potential fines for violations, which range from $10,000 to $25,000 per day (Breetz et al., 2004), the detention pond
retrofits are worth even more.
While NPSs face a total load allocation, regulations do not apply to individual NPSs. To offer incentive for NPSs to
engage in trading where they otherwise may not have any, the CCBWQA puts the implementation of the BMP and any
ensuing liability issues onto the PS project owner (Breetz et al., 2004). This incentive for the NPS places a liability is-
sue onto the PS.
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Financial incentive exists in that BMP implementation to gain credits is typically more cost-effective than PS controls
to abide by their allocated credits. The incentive is lost, however, if the PS already easily complies with its waste load
allocation. TMAL allocations were distributed with growth in mind. Trading will only achieve efficiency as this growth is
realized or the TMAL is lowered and allocations re-distributed. The relationship between PS discharge levels directly
determines the market demand for credits and the regulatory thresholds set for individual and collective PSs.
The CCBWQA is required to spend at least 60 percent of it annual budget, derived from property taxes, user fees, and
grants, on construction and maintenance of PRFs. It applies the remaining funds towards administrative costs. In 2004,
the $1,400,000 budget distributed $840,000 toward construction and maintenance of PRFs and $560,000 to administra-
tive costs. To account for anticipated future financial burdens, the CCBWQA as of 2005 has a "sinking fund" in its annual
budget. Using three-year projections, PRF costs are separated into design, capital, land acquisition, water requirements,
and O&M.The CCBWQA contributed $118,000 to the Piney Creek Stream Stabilization, which will cost $714,000 when
completed. The long-term average cost to the CCBWQA will be $115 per pound of phosphorus per year. The Cottonwood
Creek Reclamation will cost $2,100,000 with a long-term average annual cost of $330 per pound of phosphorus per
year. The Cherry Creek State Park Wetlands Project represents a capital cost of $1,928,000 with a long-term average
cost of $280 per pound of phosphorus per year (CCBWQA, 2005). The intent of these projects has not been to compete
against PS controls, but rather to supplement them in the pursuit of achieving water quality standards.
6.6 Administrative Performance
The CCBWQA must approve any withdrawal from the Phosphorus Bank. For each potential trade, approval requires a
thorough evaluation of treatment capacity and population estimates of the potential buyer as well as of the other dis-
chargers in the watershed. All activities related to a trade with the Reserve Pool also require approval by the CCBWQA,
who must consider the type of trade, corresponding trade ratios, and monitoring and reporting (CCBWQA, 2003a).
The CCBWQA conducts annual water quality monitoring in the Cherry Creek Reservoir and basin. It evaluates reser-
voir water quality, reservoir in ow and loading, surface and groundwater quality in the watershed, and effectiveness
of CCBWQA PRFs. Permits for PSs are contingent on monthly reports of 7-day and 30-day averages of phosphorus
concentrations and loadings (CCBWQA, 2003a). Continued allocation of traded credits relies on both PSs and NPSs
complying with Regulation #72 and abiding by their revised shares (Water Quality Control Commission, 2001).
Besides the CCBWQA's annual report on watershed activities, every three years the Water Quality Control Commission
must update Regulation #72 as necessary (Water Quality Control Commission, 2001). This triennial review is critical to
satisfying current needs of the dynamic basin.
6.7 Summary
The trading program has been successful in that PS phosphorus discharges with trading have remained below the
TMAL. Loads of phosphorus into the Cherry Creek Reservoir in 2004 totaled 12,512 pounds, 1,758 pounds below the
allowed 14,270 pounds. Furthermore, PRFs have proved effective, with approximate removal efficiencies as follows:
Cottonwood-Peoria Pond-42 percent, Cottonwood Perimeter Pond-22 percent, Shop Creek-63 percent, and Quincy
Drainage - 99 percent. These successes have not yet translated to compliance with the goal of 40 ug/LTP in the Cherry
Creek Reservoir (CCBWQA, 2005). This discrepancy may indicate that improvements are not immediate but rather will
emerge over time. Alternatively, internal loadings in the reservoir could be to blame, indicating that the TMAL may be
too lenient for the water body to achieve the target of 40 ug/L TP PS allocations were typically large enough to pre-
clude the need for credit purchases. Such purchases, however, may be more attractive as population growth demands
expansion of WTF capabilities. When growth of a facility exceeds the point where its discharge equals its allocations,
or when expansion occurs in a semi-urban area, which is not included in the allocated districts, interest in trades with
NPSs through the Reserve Pool will likely grow. Trading ratios can become higher depending on location within the
watershed, which suppresses trading, and more research should go into the development of the TMAL, as well as that
of conversion and trading ratios. These critical determinations would benefit from insight into fate and transport issues
such as (1) competing ions, such as magnesium (Mg+2), calcium (Ca+2), and hydrogen (H+)—i.e., those that compete
to bind with sediment and organisms; (2) biological activity; and, moreover, (3) the dynamic nature of the ecosystem.
The CCBWQA needs to take actions which would achieve short-term improvements. Decreasing the TMAL would likely
have the most dramatic effect in terms of driving trading and meeting water quality goals.
Nonetheless, the exibility of trading approaches, coupled with clear guidelines and oversight by the CCBWQA, suggests
that future success for this trading program is possible. The CCBWQA demonstrates a strong commitment to design
and implementation of its own PRFs, as well as facilitation, coordination, education, and monitoring of other potential
BMP sources in the watershed. With determination, PSs will benefit from WQT to realize water quality objectives.
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7.0 Case Study - Minnesota River and Rahr Malting Company, Minnesota -
Rahr Malting Company Water Quality Trading: A Multifaceted Success
7.1 Overview
The MPCA issued to Rahr in 1997 one of the first wastewater discharge permits in the U.S. requiring WQT. Rahr is in
Shakopee, Minnesota, in the Minneapolis-St. Paul metropolitan area (MPCA, 1997). Permit MN0031917, issued under
NPDES, stringently capped the company's oxygen-demanding discharge into the Minnesota River Basin (Figure 7-1)
(USEPA, undated). Despite the stringency, these discharge levels would still have introduced more oxygen demand
into the river than allocated by the river's TMDL, thus requiring offsets to be achieved elsewhere in the service area.
MPCA administered the federal permit and trades fundamental to the permit. Much of the nutrient loading into the basin,
which drains 16,700 square miles, derives from NPSs. In particular, nearly three-quarters of the phosphorus loading
into the river is from NPSs (MPCA, undated). In accordance with the permit, three approaches, including critical area
set-asides and wetland restoration, erosion control, and livestock exclusion, controlled phosphorus discharge into the
TMDL zone. The permit was issued in 1997 and offsets were all achieved within four years, more than a year less than
the five years it was allowed for this goal. NPS controls must remain in effect thereafter as long as Rahr continued its
discharge (Breetz et a/., 2004). Besides allowing Rahr to achieve growth and reduced costs, added benefits were the
environmental and economic improvements to the NPS areas, including restored habitats and property upgrades.
Legend
Stream
Freeway
J Watershed Boundary
Shaw
CLIENT NAME
CLENT LOCATION
FIGURE 7-1
THE MINNESOTA RIVER BASIN
Figure 7-1 The Minnesota River Basin (base map taken from http://wrc.coafes.umn.edu/lowermn/maps/mnbasin.htm)
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7.2 Background
Rahr initiated the program in an effort to increase its production by 20 percent, while gaining control and decreasing
costs of its wastewater discharge. To do so, it proposed to build its own treatment facility. Until then, the company had
sent its waste to the Blue Lake WTF in Shakopee, Minnesota, located 25 miles upstream from the con uence of the
Minnesota and Mississippi Rivers. The Metropolitan Council Environmental Services operated the WTF. Significant stress
to dissolved oxygen levels to below acceptable levels due to nutrients in the lower Minnesota River, below mile 25, led
to the implementation in 1988 of the TMDL for five-day CBOD (CBOD5).20TheTMDL had allocated 53,400 pounds per
day of CBOD at mile 25 and downstream. This allocation was based on the 7-day, 10-year low ow in 1988 because
low- ow periods are when dissolved oxygen levels are most vulnerable (Faeth, 2000; Jaksch, 2000). Excessive oxygen
demand results in dissolved oxygen levels that do not adequately support aquatic life. Phosphorus loads contribute
to the CBOD. Additional stress to the dissolved oxygen levels result from nitrogen and sediment loads, which deplete
oxygen from the river water via nitrogenous biochemical oxygen demand (NBOD)21 and sediment oxygen demand.22 The
TMDL obligated MPCA to prohibit new oxygen demanding loads into the river. Therefore, any new discharges would
require an existing source to be eliminated.
The key impetus for implementing the program was the infeasibility of Rahr to reduce down to zero the pollutant loads
in the ef uent from its planned WTF. Therefore, Rahr needed to somehow reduce other loads into the river to offset
its own. Blue Lake WTF would not agree to trade any of its allocated loading because it was needed to accommodate
growth. The company negotiated an agreement with MPCA to offset CBODs discharge from its new WWTP by funding
upstream NPS phosphorus reductions. Under this agreement, Rahr developed the program to treat its process waste-
water to within specified levels and reduce upstream loading by an amount equal to its resulting discharges (Fang and
Easter, 2003).
The resulting trade included fourNPSs upstream of the TMDL zone. Rahr was the sole PS. While nitrogen and sediment
were also included in the trades prescribed in the permit, phosphorus is the nutrient traded in the chosen BMP.
7.3 Program Performance
The trading program was a multifaceted success due to diligent efforts by all those involved to maximize and balance
efficiency, equivalency, additionality, and accountability (Fang and Easter, 2003). These four criteria are fundamental to
a successful trading program involving NPSs.
The first criterion is one of economics. Efficiency mandates the trade proceed only when one source is able to more
cost-effectively reduce its discharges than another source. This condition is critical to making the program financially
attractive, and thus marketable. Although Rahr had no alternative but to buy credits from NPSs, in contrast to market-
based systems where there is a choice of whether or not to trade at all, it had to optimize cost-effectiveness in the types
and locations of NPS controls. NPSs, which are not presently regulated, typically have little incentive to control their
discharges with the high costs involved in trading. Indeed, there may be disincentives in participating in such trades. In
particular, by agreeing to a quantified load reduction, an NPS discharger may unintentionally facilitate future regulation
of that discharge. Rahr was fortunate to have found the trading partners that it did. This good fortune was the result of
actively involving the community and environmental organizations throughout the process, promoting Rahr's position to
fund the BMPs, financially compensating the NPSs, and avoiding quantified validation of load reductions. So while the
NPSs were not driven by regulation, they recognized the opportunity to improve their property free of charge without
acknowledging measurability of their loads.
The other three criteria address technical and administrative issues necessary to evaluate efficiency. Equivalency is a
measure of how pollutant loads from various sources relate to the pollutant of concern to be offset. Ensuring that offsets
are equivalent to or greater than the permitted load is vital to avoid exceeding the TMDL. Conversion ratios multiply
the offsets to account for uncertainties associated with temporal, spatial, and/or chemical differences in the sources.
Such differences are often complex, so this criterion is fraught with uncertainties, which must also be factored into the
trade. Additionality stipulates that any NPS offset that would have occurred regardless of the trading program cannot
count toward a trade. This prevents double-counting actions simultaneously applied to more than one objective. Finally,
accountability mandates appropriate monitoring and oversight to ensure proper implementation of all program require-
ments. Performance and design monitoring and reporting may satisfy this criterion. Otherwise, conservatively setting
20 CBOD is the amount of dissolved oxygen that is needed for the breakdown of carbon-based organic molecules into CO2 and
water.
21 NBOD is the amount of dissolved oxygen that is needed for the breakdown of nitrogen-based protein molecules and ammonia
into nitrate and nitrite. Nitrogen conversions use four times as much oxygen as carbon conversions.
22 Sediment oxygen demand is the amount of dissolved oxygen that is needed for biological and chemical processes in the sedi-
ment.
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the conversion and trading ratios could satisfy this criterion by overshooting expected requirements to offset uncertainty
in performance (Fang and Easter, 2003; Jaksch, 2000).
The following sections describe how, the four criteria for a successful WQT program were optimized through scientific
research, cooperation by all those involved and assurances of financially viability, this laid the foundation forthe program's
success. A quasi-independent five-person board was set up to select sites for trading consideration. A technical con-
sultant with a member on the board calculated trading units. For a trade to be pursued, MPCA needed first to approve
it, followed by a positive vote by the board, followed again by final MPCA approval (Jaksch, 2000). Common objectives
to conservatively protect and even improve the environment, reliable science, and the social and financial commitment
by Rahr and MPCA supported the WQT program. Rahr offset the wastewater load that it planned to add to the river by
funding BMPs to decrease NPS loads upstream of the facility. After careful consideration of several types of BMPs, four
trades were chosen for their ability to achieve the four criteria, particularly equivalence and accountability.
Despite the overall success of the program, some challenges were encountered. As demonstrated in the following sec-
tions, complexities involved in the determination of conversion and trading ratios hindered the certainty of equivalency.
Furthermore, efforts to develop scientifically-based ratios burdened the program, particularly MPCA, with transaction
costs. Another limitation was the lack of necessity of NPSs, which are generally not regulated, to work within set credits.
Although they did not have the market-based incentives to trade with Rahr, they were motivated by financial compensa-
tions and improvements to their property. Still, Rahr was fortunate to have contracted with those that it did. However,
future trading partners, either to allow for growth or if further reductions are necessary, may be more challenging to
convince. Finally, being one of the first in the nation to trade nutrients, and the first to do so trading pollutants other
than that targeted by the TMDL, made additional research and negotiation necessary which added another obstacle,
and thus time and money.
7.4 Technical Performance
MPCA and Rahr agreed on a trading credit system where one credit unit is equivalent to one pound per day of CBODs.
A critical component of the trading program was the determination of reasonable ef uent levels from their planned PS.
The concentrations of CBODs, phosphorus, nitrogen, and TSS in 24-hour composite samples of their treated waste
were analyzed three times per week. Monthly concentrations of CBODs for average (1 million gallons per day [mgd]) and
maximum (2.5 mgd) ows could not exceed 12 mg/L and 18 mg/L, respectively. These limits were enforced year-round,
more stringent than the typical increase during October through May. Also more stringent was the limit for phosphorus,
set at 2 mg/L, compared to the more common limit of 3 mg/L. Ef uent limits were 30 mg/L and 45 mg/L of TSS for
average and maximum ows. Ef uent limits for nitrogen depended not on ows but on the time of year, decreasing in
warmer months, and with a yearly average of 9 mg/L. So for every unit discharged by Rahr, BMPs had to control an equal
number of units of NPS discharges upstream of the facility. After treating its waste, Rahr would still need to discharge
54,750 pounds of CBODs per year into the TMDL zone (Jaksch, 2000), equivalent to 150 units.
The permit specifies that BMPs use soil erosion control; livestock management to exclude cattle from stream or riparian
zones either with or without rotational grazing; critical area set-asides; and/or constructed/restored wetlands (MPCA,
1997). The nature of CBOD challenges the certainty of equivalency in that nutrient and sediment loads relate accord-
ing to site-specific factors to the oxygen demand. To select the appropriate BMPs to pursue, the permit prescribes the
relationships between loads of phosphorus, nitrogen, sediment, and CBODs. Furthermore, the program incorporated
several safety factors to provide accountability by reducing risks to equivalency. Conservative ratios used to determine
equivalency made it unnecessary to monitor BMP load reductions, thereby saving MPCA time and money. Equation 7-1
calculates the number of units traded to offset the PS discharge.
CR
trade_unitCBOD5 =pounds_per_daypollutant_reduced.— (7-1)
where trade_unitOBOD5 = trading units (defined as pounds of CBODs per day)
pounds_per_daypollutant reduced = pounds per day of the pollutant reduced by BMPs
CR = conversion ratio'
TR = trading ratio
Conversion ratios for phosphorus relied on research relating phosphorus with chlorophyll concentrations, which in turn
relate to CBOD. Therefore, calculated ratios of phosphorus loads to CBOD determine the trading ratios. This ratio varies
with biological activity, ow rate, turbidity, phosphorus bioavailability, and concentrations of other nutrients. Approximately
15 miles upstream of the facility, at Jordan, 1 pound of phosphorus reduced from the NPS was worth 8 pounds of
CBODs per day, i.e., 8 units. Although this ratio varied between 1:8 and 1:17, as determined presumably by measured
concentrations of phosphorus and chlorophyll and an average stream correlation between chlorophyll and CBOD, the
ratio was conservatively established as 1:8 (Jaksch, 2000). Unfortunately, this conversion does not directly address the
differences in phosphorus bioavailability of loads from various sources, i.e., dissolved or bound to sediment. The impacts
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on oxygen demand and river conditions differ according to complex dynamics that conservative assumptions may not
always manage. It was assumed that use of the most conservative ratio would adequately offset uncertainty associated
with site-to-site differences. This assumption was not explicitly validated through performance monitoring. Some critics
consider this failure to validate the performance a critical fault in the program, while others worry that overly conservative
assumptions eliminate otherwise viable potential NPS trading participants. In all fairness, WQT should not be required
to satisfy a higher degree of technical rigor, in terms of modeling and monitoring than was originally applied in the first
place during development of the TMDL and individual load allocations.
Conversion ratios for nitrogen relied on stoichiometry, which dictates 4.6 pounds of oxygen for every pound of TN.
However, nitrogen exerts oxygen demand more rapidly than does phosphorus. Additionally, nitrogen leaves the system
through volatilization, leaving less to demand oxygen. Therefore, nitrogen upstream of mile 25 trades for less than it does
downstream of mile 25. Conservatively, the ratio was established as 1:4 downstream and 1:1 upstream, i.e., 1 pound
per day of reduced nitrogen was worth four units downstream and one unit upstream (Jaksch, 2000).
Sediment was related to CBODs on a 1:0.5 ratio. Reducing the sediment load by 1 pound per day counted as reducing
0.5 pounds of CBODs (Jaksch, 2000). This conversion re ects that sediment demands much less oxygen than do the
nutrients.
Finally, measured CBODs was traded variably depending on the location along the river, with a 1:1 ratio at mile 25 and
downstream, decreasing to 1:0.01 at mile 107 (Jaksch, 2000). The decrease is justified by the CBOD upstream exerting
its oxygen demand before the TMDL zone.
Load reductions for each BMP proposed for implementation were not measured but were instead estimated according
to several assumptions. Safety factors aim to counter the uncertainty that these assumptions bring. Trades defaulted
to a trading ratio of 2:1, so that two units of NPS reduction were needed for every unit that the PS discharged (Kieser
and Fang, 2005). As appropriate, additional safety factors were multiplied into the trading ratios. Phosphorus reductions
from soil erosion were estimated based on analyses of phosphorus contents of soil and measured soil loss reductions.
This estimation incorporated an additional safety factor of 0.75 for samples that indicated relatively high phosphorus
concentrations, thus reducing the amount of CBODs that would be credited for each pound of offset phosphorus. For
livestock exclusion approaches, pollutant loadings into the river are calculated as the product of the area's delivery
ratio, the time livestock spend on the land, and the size of the herd. The offset is thus the difference of these estimates
from before and after the controls are implemented. Typically, depending on the time of year, cattle spend 25 percent
to 36 percent of their time in the riparian zone. Delivery ratios are 100 percent within the riparian zone, 20 percent out-
side the riparian zone but within 0.25 miles of the stream, and 10 percent beyond that (Jaksch, 2000). Rahrand MPCA
agreed through negotiation to use conservative conversion and trading ratios to provide accountability, supplanting the
need to validate these load reductions through onsite monitoring of CBODs load reductions.
Based on an optimization of the four criteria, the board identified and MPCA verified four NPSs for trading: (1) Cotton-
wood River, (2) Minnesota River, (3) the Fruhwirth site along Eight Mile Creek, and (4) the Hathaway site along Rush
River (Fang and Easter, 2003). Figure 7-2 identifies approximate locations of these sites relative to the Rahr facility.
BMP approaches included critical area set-asides with revegetation, erosion control, and livestock management. The
chosen BMPs at these sites would not have been implemented were it not for the trades, satisfying the additionality
criterion. A contract with Rahr for long-term commitment to these BMPs, the ability to monitor these sites, and oversight
by the board and MPCA added a greater level of accountability. To assure accountability, Rahr must submit monthly
monitoring reports, as well as annual reports of reductions of CBODs from the NPSs.
While the permit stipulates the conversion and safety factors for nitrogen, sediment, and CBODs, the BMPs pursued
for trading achieved all the necessary credits by reducing only phosphorus input to the TMDL zone. According to the
1:8 ratio for phosphorus:CBODs, the reduction of 97,730 pounds of phosphorus measured over five years is equivalent
to reducing 781,830 pounds of CBODs over the same time period, which averages to 428.4 pounds of CBODs per day
(Fang and Easter, 2003). Using the trading ratio of 2:1, this equates to 214.2 units, far exceeding the 150 units man-
dated in the permit. Table 7-1 itemizes the pounds of phosphorus and consequently CBODs over the five-year permitted
timeframe. Table 7-2 itemizes the resulting credits that these sources earned for Rahr within that period.
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Minnesota River site
Eight Mils Creek sits
in New Ulm
The Minnesota River
Basin
Rahr facility in
Shakopee (Mile 25)
__t Wfotonwan Rivff
/ Watershed
Cottonwood River site/
near New Ulm ^*™
Rush River site
near Henderson
Note: Labeled site locations are approximate.
Figure 7-2 The Minnesota River Basin with sites of NFS sellers identified (base map taken from
http://wrc. coafes. umn.edu/lowermn/maps/mnbasin. htm).
Along the Cottonwood River, which ows east to the con uence with the Minnesota River near New Ulm, Minnesota,
and the Minnesota River at approximately mile 150, also near New Ulm, Minnesota, easements set aside approximately
105 acres of critical areas from crop production to prevent ood scouring. These areas were, in essence, 105 acres of
restored wetlands. Plowing for crop production contributed to coding, which resulted in the removal of several feet of
soil (Jaksch, 2000). Restoring native wetland vegetation on farmland along the rivers protected these critical areas from
further scouring. Together, these wetlands removed 45,944 pounds of phosphorus over five years, generating approxi-
mately 100 units of credit. Rahr ultimately donated these restored wetlands to the city of New Ulm to be used as a park,
and to the Coalition for a Clean Minnesota River, a local environmental organization, to be used as an environmental
education site (Breetz et a/., 2004). Restoring these wetland sites also created habitat for wildlife. The effectiveness of
these restored wetlands for reducing nutrient loading was assumed based on conservative performance ratios and was
not validated by performance monitoring data (Fang and Easter, 2003).
Soil erosion controls restored stream banks along Eight Mile Creek at New Ulm, Minnesota, and along Rush River in
Henderson, Minnesota. Controls included bioengineered banks with vegetation and J-hooks in the river to de ect ow
energy. The former also managed livestock by re-grading the feedlot for wastes to ow away from the water, and fencing
in the cattle to exclude them from the riparian zone, which had been overgrazed (Jaksch, 2000). Aerial photographs
spanning 36 years and periods of high and low ows were used to estimate the average bank recession rate. The lifetime
of the control structures is comparable to this duration, rendering the estimates of the credits more reliable. In addition
to offsetting sediment loads, the landowners of these source control sites received the added benefit of preserving the
land against erosion. Since 1988, they had unsuccessfully sought financial means to control bank erosion. The erosion
was sometimes so extreme that it impacted adjacent land, destroying houses and barns (Breetz et a/., 2004; Fang and
Easter, 2003). The BMPs for Rahr's permit were able to stabilize the banks within two years for the Eight Mile Creek
site and four years for the Rush River site.
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Table 7-1 Pounds of Phosphorus and CBODs Reduced over Five Years
Pounds of CBODS
Pounds of phosphorus
Cottonwood
105,490
13,190
Minnesota
262,070
32,760
8-Mile Creek
54,020
6,750
Rush River
360,260
45,030
Total
781,840
97,730
Table 7-2 Traded Units From Each Controlled Nonpoint Source
Traded units
CBODS pounds per day
Phosphorus pounds per day
Cottonwood
28.9
57.8
7.2
Minnesota
71.8
143.6
17.9
8-Mile Creek
14.8
29.6
3.7
Rush River
98.7
197.4
24.7
Total
214.2
428.4
53.5
7.5 Economic Performance
At MPCA's instruction, Rahr established a trust fund of $250,000 to secure monies to develop and maintain BMPs. The
five-person board charged with selecting sites also managed this fund, offering credibility and unbiased views to plan-
ning and implementation. However, the inclusion of one executive from Rahr communicated to the public the company's
commitment to the environment while advancing the company's interests in decisions. The fund was to cover all expenses
of designing and implementing the trades, barring transaction costs (Kieser and Fang, 2005). If costs exceeded the
fund's capability, Rahr was responsible for the difference.
Transaction costs added an estimated $105,000, or 35 percent, to the cost of the controls, for a total cost of $405,100,
most of which MPCA and Rahr incurred. The product of the median salary rates of Rahr and MPCA staff members and
their estimated time spent on transaction activities provided an estimate of their respective transaction costs (Fang and
Easter, 2003). Engineering, material, and consulting costs were not considered transaction costs and were instead covered
by the trust fund. The relatively small number of trades, as compared to other trading programs, such as the Southern
Minnesota Beet Sugar Cooperative in Minnesota, with over 100 trades, simplified the process somewhat. However, the
complexities of trading ratios for equivalency and safety factors for accountability added significant costs.
The permit phase spanned from the initial negotiations to when the permit was issued. This phase also included the
search for trading partners, administration, and communications between Rahr and state and federal authorities. As
this was one of the first of its kind, this phase took about two years and amounted to approximately 65 percent of the
transaction costs. Following permitting, implementation was the phase during which the trades occurred and credit re-
quirements were fulfilled with implementation of nutrient control measures. Costs went to credit verification and project
management. As MPCA took charge of the design on the BMP and trading structure, their transaction costs accounted
for 81 percent of the total, leaving Rahr responsible for less than 20 percent of the total (Jaksch, 2000).
The cost of credits was estimated based on the capital and O&M costs of the project, the estimated pounds of offset
nutrients it could deliver, trading ratios, and safety factors. Without transaction costs, the critical area set-asides with
restored vegetation along the Cottonwood and Minnesota Rivers were most cost-effective. By reducing phosphorus load-
ings into the TMDL zone, these restored wetlands cost $4.44 per pound of phosphorus over the five years of the permit.
The cost per pound of reduced phosphorus at the Fruhwirth site along Eight Mile Creek and the Hathaway site along
Rush River were $5.28 and $4.49 per pound, respectively. Accounting for the 1:8 conversion ratio with CBODs, credits
averaged $0.77 per pound of CBODs removed. However, the BMPs will likely survive and remain effective far beyond
the five years of the permit. Reasonably assuming a 20-year lifetime, with an 8 percent discount rate, the average cost
of reduction decreases to $0.20 per pound of CBODs and $1.56 per pound of phosphorus. Adding transaction costs,
these reductions increase to $1.03 per pound of CBODs, equivalent to $0.26 per pound of CBODs over 20 years, and
$8.26 per pound of phosphorus, equivalent to $2.10 per pound of phosphorus over 20 years. The long-term measures
such as easements and re-vegetation are the most efficient of the BMPs because they provide greater nutrient reduction
with low investment. Furthermore, the lifetime of these controls is comparable to the lifetime of the nutrient reduction
estimation, minimizing the uncertainties associated with the trade (Fang and Easter, 2003).
In contrast, a comparable municipal WWTP designed for permitted discharge of 1.5 mgd would have to meet 1 mg/L
phosphorus if only PSs were responsible for phosphorus load reductions. Over 20 years, and at an 8 percent interest
rate, the capital and operational costs associated with implementing these controls would be between $4 and $18 per
pound of phosphorus. The NPS controls are thus more cost-effective than PS controls even when transaction costs are
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considered. In fact, the savings afforded to Rahr for not using Blue Lake's services, accounting for the cost of its new
facility and the $250,000 to fund the trust, will amount to more than $300,000 per year over 30 years (Jaksch, 2000).
7.6 Administrative Performance
The five-person board was involved in every step of the process, from recommending preliminary NPSs for review to
selecting the final projects to implement. MPCA framed the trade within the NPDES structure, thereby underscoring
accountability. To ensure legal enforceability of the selected controls, the NPDES permit prescribed the types of BMPs,
selection process, reporting, and goals. MPCA was charged with verifying each trade and confirming annual pollutant
reductions prescribed in the permit (Breetz et a/., 2004). While the credits must be achieved within five years of permit
issuance, Rahr must continue O&M of BMPs for as long as it discharges within the TMDL zone.
Administration of the trade provided exibility to encourage success. Credits from the NPS controls were awarded on
a partial basis as projects progressed (Breetz et al., 2004). Moreover, MPCA offered Rahr 30 units of credits from the
yearly cumulative load reductions for CBODs and another 30 units of credit for phosphorus for consenting to the more
stringent point discharge ef uents of each. These credits started with 2001, the year of permit expiration, and continued
yearly thereafter, provided the point ef uent levels were met. As such, if Rahr accepted all of these offered credits, NPS
controls would only need to offset 90 units. Rahr was also offered 10 units of phosphorus credit to be used in 1998,
1999, or 2000 to make up for any deficit in those years. Finally, 20 units of credit were issued to Rahr for starting up its
facility after 1997. The permit offered financial incentives to Rahr to efficiently achieve the mandated 150 units of credit
through BMPs within the permit's five-year life. MPCA would give the company an additional five years to completely
spend any of the remaining $250,000 (Fang and Easter, 2003).
7.7 Summary
According to the conservative assumptions, but not through validated monitoring, the program successfully reduced the
NPS load by more and in less time than the permit required. Cooperation by farmers, landowners, grass-roots environ-
mental organizations, and eagerness of Rahr to work with, not against, all stakeholders, contributed to the program's
success. The nutrient offset achieved by the NPS controls allowed the Rahr facility in Shakopee to grow according to
Rahr's original treatment facility design. Rahr has become the largest producer of malt at a single site in the world. In the
process, it has earned the reputation of working with and for the community. The NPS controls also provided environ-
mental and social benefits. The public became aware of the unregulated nutrients discharged by NPSs. Involving public
interest groups early during the negotiation phase educated many on the challenges and significance of equivalency,
additionality, and accountability. The controls also served to create wildlife habitat. The trading program benefited the
financial and social standing of Rahr, water quality, and the community.
Even with its success, the program encountered some limitations. As one of the first of its kind, this trading program
faced new challenges. Fortunately, lessons learned from Rahr's trade could be extrapolated to other programs. A pri-
mary gap hindering the full potential of NPS trades was the inability to accurately quantify differences in nutrient load
reduction associated with dynamic complexities that vary from site to site. Such uncertainties were offset by increasing
the scale of each BMP (e.g., restore a larger wetland area to offset uncertainty in performance). The expenses incurred
in efforts to conservatively overcome these uncertainties further burdened the program. Another limitation is that NPSs
typically lack regulatory incentive to engage in trading. Rahr will have to overcome this for any future reductions it may
need. Nonetheless, the benefits far outweighed the limitations, rendering this trading case a success.
On December 1, 2005, MPCA issued a general NPDES permit (MNG420000) to all authorized parties within the Min-
nesota River Basin, which included Rahr, who may apply for a permit to discharge phosphorus. This permit aims to
achieve the renewed TMDL there. Moreover, the permit specifically authorizes WQT according to specified units of credit.
Individual permits must still be obtained and remain valid for another five years, through November 30, 2010 (MPCA,
2005). The general permit is consistent with the continued impairment for oxygen deficiency, albeit with indications of
some improvement, and the significant blame that falls on phosphorus discharge (MPCAef a/., 2003). Moreover, it gives
credence to the validity of trading for which Rahr was a pioneer.
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8.0 Case Study - Lower Boise River, Idaho
8.1 Overview
The LBR Ef uent Trading Demonstration Project is the first WQT project in the Pacific Northwest (USEPA, 2002c).
The project is a start-up program for phosphorus trading in the LBR watershed in Idaho. The goal of the project is to
create a business-like trading framework that can be implemented to help achieve the nutrient reduction goals set by
CWA Section 303(d). The project is designed to be environmentally and legally sound, consistent with existing regula-
tory programs, allow trades to occur in a dynamic, market-based manner, and grounded in environmentally protective
requirements. Furthermore, project participants hoped the WQT framework developed by the LBR project could guide
similar programs in other areas in the region and throughout the country.
8.1.1 Location
The LBR Watershed is located in the southwestern part of Idaho and encompasses 1,290 square miles (Figure 8-1).
The LBR ows through the watershed for 64 miles, crossing through Ada County, Canyon County, and the city of Boise.
The river ows to the northwest from its origin at Lucky Peak Dam to its con uence with the Snake River near Parma,
Idaho. Nine cities are located within the watershed, most adjacent to Boise River. The watershed is home to about one-
third of Idaho's population and is growing rapidly (Ross and Associates, 2000). Major land uses in the subbasin include
forestry, agriculture, gazing, and urban development. There are 15 subwatersheds within the watershed, and 4 stream
segments are listed on the 303(d) list for pollutants of concern, including ow alteration, sediment, dissolved oxygen, oil
and grease, nutrients, bacteria, and temperature. The trading demonstration project is designed to address one of the
nutrient pollutants of concern - phosphorus. The project is proposed to help comply with the current policy of "no net
increase" in TP established in the sediment and bacteria TMDL for LBR completed in 1998 and approved by USEPA
in 2000 (IDEQ, 2005a). An LBR phosphorus TMDL is anticipated now that the downstream Snake River-Hells Canyon
(SR-HC) TMDL has been issued (September 2004). This LBR phosphorus TMDL was expected to be completed by
IDEQ for review by USEPA in March 2006 (Schary, 2005).
Ltqend
Stream
Interstate
MgOroy
courty
WatenfM Boundary
Figure 8-1. Lower Boise, Idaho river watershed site map.
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8.1.2 Participants
USEPA started collaborating with Idaho, Oregon, and Washington in late 1997 to examine how WQT could reduce the
cost of meeting TMDL requirements in the Pacific Northwest USEPA Region 10 (excluding Alaska) (Ross and Associates,
2000). USEPA worked with IDEQ to launch the LBR Ef uent Trading Demonstration Project as the first pilot project for
the region (Breetz et a/., 2004). IDEQ assumed responsibility for the project from USEPA on April 21, 2000 by signing
an interagency agreement (IDEQ, 2001). Other agencies participating in the interagency agreement included USEPA,
ISCC, NRCS, Ada Soil and Water Conservation District (ASWCD), Canyon Soil and Water Conservation District (CSCD),
Southwest Idaho Resource Conservation & Development Council, and the US Bureau of Reclamation. This interagency
agreement outlined the various responsibilities of the agencies for continuing to support the demonstration project.
Idaho LBR was selected as the first demonstration project based on several criteria and support from interested parties
(Ross and Associates, 2000). The project began in January 1998 with the assessment of the market feasibility of phos-
phorus trading. Starting in August 1998, the trading structure and protocols were developed and tested on two trading
simulations. The results of this development and testing were summarized in September 2000 (Ross and Associates,
2000). Trading is scheduled to begin following completion of the LBR phosphorus TMDL and issuance of new NPDES
permits, which are still pending.
8.1.3 Administration
The trading project is set up to be administered by the Idaho Clean Water Cooperative (ICWC), a newly created non-
profit association (ICWC, 2000). The concept for giving administrative responsibility to a non-profit non-governmental
group was generated to reduce the fears of trading partners of government intervention (Kieser and Fang, 2005). A
Memorandum of Understanding (MOU) between USEPA, IDEQ, and ISCC signed April 27, 2001 also governs the proj-
ect. This MOU defines the roles of the agencies in verifying credits purchased and used by NPDES-permitted sources
that choose to participate in the WQT project.
8.2 Background
The LBR is highly enriched with phosphorus, especially at the downstream cities of Middleton and Parma. Water high
in nutrients such as phosphorus can cause eutrophication.This condition can lead to algal blooms, which can harm fish
by reducing oxygen levels within the water when the algae dies and decomposes. This reduction in oxygen is caused
by the heavy oxygen demand from microorganisms as they decompose the organic material. Algal blooms can also
interfere with water use for recreation as the vegetation disrupts equipment and swimming. The foul smell of decomposi-
tion also disrupts recreation. Consequently, nutrients like phosphorus contained in runoff and erosion from NPSs, such
as agriculture, create a resource management concern. In general, phosphorus bound to sediment contributes 60 to
90 percent of the phosphorus in runoff from most cultivated land (NRCS, 2001).
Recent analysis by IDEQ indicated that the phosphorus level is not currently high enough in LBR to cause algal blooms,
but contributes to the high phosphorus loads downstream in the Snake River (IDEQ, 2005b).The phosphorus loads in
Snake River are problematic and require reduction by more than 78 percent. Because LBR is the largest contributor of
phosphorus to the Snake River, phosphorus loads in LBR will need to be reduced by the same amount (IDEQ, 2005b).
The SR-HC TMDL targets each tributary to contribute less than or equal to 0.070 mg/L phosphorus as measured at the
mouth of the tributary between May and September. Studies in the LBR watershed found that phosphorus concentra-
tions along LBR increase by more than 10-fold, from over 0.02 mg/L near Boise to 0.26 mg/L near the LBR's con uence
with the Snake River (IDEQ, 2005b).
8.2.1 Phosphorus Movement
Within the LBR and Snake River, phosphorus is the limiting nutrient, and any increase can result in greater growth of
aquatic vegetation. The amount of phosphorus in the system depends on the transport of phosphorus to the water body;
the source and form of phosphorus; and management factors such as application, timing, and placement in the landscape.
Dissolved phosphorus is readily available to plants, while particulate phosphorus (attached to sediment) can be a long-
term source of phosphorus within a system (NRCS, 2001). The ability of a water body to handle inputs of phosphorus
depends on the volume of water present, the temperature of the water to promote algal blooms, and the turbidity of
water (phosphorus tends to bind to sediment particles). Typically highest concentrations of phosphorus happen during
low- ow conditions, which typically occur during the winter when aquatic plant growth is less of a concern. However, in
the LBR and Snake River low- ow conditions can also occur during summer droughts, allowing algae to thrive.
The LBR is the greatest contributor of phosphorus to the Brownlee Reservoir via the Snake River. This reservoir suffers
from excessive nutrient loading and nuisance aquatic growth. Idaho law requires surface waters of the state to be free
from excess nutrients that can cause visible slime growths or other nuisance aquatic growths, impairing designated
beneficial uses (Idaho Administrative Procedures Act [IDAPA] 16.01.02.200.06). The nutrient data of Boise River and
productivity in the lower Snake River indicate that a cap on phosphorus is needed for the LBR. Thus, the LBR sediment
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and bacteria TMDL established a policy of "no net increase" of TP as an interim measure until the Snake River basin-
wide nutrient goals are set (IDEQ, 1999). Now that the phosphorus TMDL is completed for SR-HC, the phosphorus
reduction goal for a LBR's phosphorus TMDL will be adjusted and finalized (Breetz et a/., 2004). This goal is expected
to be approximately an 80 percent reduction in phosphorus at the mouth of LBR (Schary, 2005).
8.2.2 Trading
Exploring a WQT program as a water quality management tool was jointly supported by USEPA and by Idaho, Oregon,
and Washington water quality programs. Motivation for this innovative tool was generated by the considerable chal-
lenges produced during the development and implementation of TMDLs on court-order schedules (Ross and Associates,
2000). WQT was considered a exible and cost-effective option to meet the policy of "no net increase" in phosphorus
established by the LBR sediment and bacteria TMDL and expected in the LBR phosphorus TMDL.
8.2.3 Regulations
There are several regulatory drivers for the LBR WQT project. In addition to the CWA and Idaho law mentioned before,
Idaho state rules call for "no net increase" in phosphorus for the LBR (IDAPA 16.01.02.054). These rules also specifi-
cally allow WQT as a tool for meeting the "no net increase" requirement. The rules establish a source-specific cap on
phosphorus discharges to the Boise River. PSs are allocated phosphorus reductions based on TMDL requirements
within their NPDES permit. Since Idaho is not a delegated state for NPDES permits, these permits are issued by USEPA
Region 10. It is expected that NPSs may also be subject to a load allocation for phosphorus in the future (Ross and
Associates, 2000).
8.2.4 Trading Framework
The Idaho LBR Ef uent Trading Demonstration Project is an example of interagency collaboration to produce a trading
framework that can be used for WQT in LBR. The lessons learned during this framework development and the frame-
work itself can apply to other areas of Idaho, the Pacific Northwest, and the United States, although local and regional
conditions, regulations, needs, and acceptance will affect its applicability.
The LBR project participants agreed on several objectives during the process of developing a trading framework for
LBR. These objectives were to create a framework that:
• Is legally defensible and enforceable;
• Protects water quality;
• Maximizes market exibility and minimizes transaction costs;
• Ensures trading activities are apparent to the public;
• Does not create or exacerbate other environmental problems; and
• Supports robust participation.
The project also developed a set of design principles that promoted trade and cost-effective implementation of TMDL
reductions. These principles are as follows:
• Avoid trade-by-trade changes to the TMDL;
• Avoid trade-by-trade changes to the NPDES permits;
• Minimize trades through private contracts;
• Create environmentally equivalent (or better) reductions;
• Work with existing programs and processes; and
• Provide clear and predictable permit compliance and enforcement.
Features of the Idaho LBR trading framework and demonstration project include:
• Regulatory guidance by USEPA's Final Water Quality Trading Policy (2003);
• Regulatory guidance by IDEQ's Pollutant Trading Guidance (2003);
• Trading project administration by non-profit association: ICWC;
• Preparation of TMDLs, implementation plans, and trading ratios by IDEQ;
• Issuance of NPDES permits and approval of TMDLs by USEPA;
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• Approved list of BMPs with effectiveness calculations and uncertainty discounts by ISCC (2002);
• Guidance for ICWC provided by council from NRCS; and
• Purchasers include seven POTWs, three industrial dischargers, and eight irrigation districts.
No trades have yet been made using the LBR Ef uent Trading Project because of delays in finalizing the LBR phosphorus
TMDL. Therefore, no information is available yet on what portion of the project is composed of PS or NPS trades. The
expected purchasers and the abundance of agriculture create an environment favorable for producing trading partners.
Furthermore, the stringent target set by the SR-HC phosphorus TMDL will be difficult for PSs to meet without seeking
trades, especially for the final portion of phosphorus reduction (Schary, 2005). Consequently, once the regulatory driv-
ers are in place, trading should commence relatively quickly.
8.3 Program Performance
The LBR Ef uent Trading Demonstration Project set up a framework for trading pollutant discharges among sources.
The framework allows for trades among point and nonpoint pollutant generators. Elements of a trading process were
developed by the project team, including permit conditions, necessary forms, agencies' roles, and generation of credits.
To understand the estimated cost savings of implementing a trading program, municipalities were asked to consider the
impacts of phosphorus reductions on their programs and estimated a unit cost of $12 to $178 per pound of phosphorus
reduction. Project participants estimated the cost for NPSs to reduce phosphorus through BMPs ranged from $2 to $20
per pound. Thus, the estimated cost savings from implementing the trading project in LBR are estimated to be $10 to
$158 per pound of phosphorus reduction.
8.3.1 Trading Process
The framework established by the demonstration project generated a straightforward process to complete a trade. Steps
for PS to NPS trade include:
1. Trading parties are identified;
2. Water quality contribution is calculated or measured for NPS participants;
3. Trading parties negotiate and sign trade contract;
4. Seller installs phosphorus reduction measure (if not already in place);
5. NPS BMP installation inspection/buyer signs and submits first "Reduction Credit Certificate;"
6. Buyer and seller parties sign and submit official "Trade Notification Form;"
7. Trade information is entered into Trade Database (monthly); and
8. The ICWC tracks trading activity and USEPA audits trades though NPDES permits.
The ISCC inspects BMPs installed by NPSs to document proper design, monitoring, and maintenance. These inspection
reports are reviewed by USEPA and IDEQ to verify the BMP implementation. The agencies may also visit BMP sites
to confirm their performance. NPDES permit holders are ultimately responsible for ensuring proper implementation of
BMPs. Consequently, they inspect the BMP installation and receive copies of ISCC's inspection reports. USEPA and
IDEQ take up any compliance matters or enforcement actions with the NPDES permit holder, not the BMP installer
(USEPA, 2002c).
The ICWC is responsible for tracking trading activity and maintaining a trade tracking database (USEPA, 2002c). The
major functions of the ICWC are to:
• Set a submittal time for trade notification forms and reduction credit certificates;
• Accept and review trades to ensure completeness and consistency with trading project requirements, and not ac-
cept trades that do not meet the project requirements;
• Track all trades in a central database and determine how trades impact ef uent limits and account balances of
buyers and sellers;
• Reconcile all trades in the market area to ensure credits are not used more than once;
• Make trading information and adjusted ef uent limits readily available to regulatory agencies and the public; and
• Produce Trade Summary Reports required for NPDES permit compliance and provide them to the PSs involved in
trades.
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8.3.2 BMPs
The ISCC, in collaboration with IDEQ, developed eligible BMPs for the LBR Pollution Trading Project (ISCC, 2002). The
BMPs listed in the state-level Idaho Pollutant Trading Guidance were broken down by region because the "effective-
ness" of the BMP would be different in each region (IDEQ, 2001). Several NPS BMPs are eligible for offsetting a PS
discharge. Eligible BMPs available to trading contracts are listed in Table 8-1:
Table 8-1 Currently Eligible BMPs for Trading in LBR WQT Project3
BMP
Sediment basins
Filter strips
Underground outlet
Straw in furrows
Crop sequencing
Polyacrylamide
Sprinkler irrigation
Microirrigation
Tailwater recovery
Surge irrigation
Nutrient management
Constructed wetland
Effectiveness (%)b
65-85c
55
85-65d
Not listed
90
95
100
100
100
50
NA
Not recommended - 90e
Uncertainty Discount (%)b
10-15C
15
15-25d
Not listed
10
10
10
2
5
5
NA
Not recommended-5e
Life span
20 years
1 season
20 years
1 season
1 season
1 irrigation
15 years
10 years
15 years
15 years
1 years
15 years
a Source: http://www.envtn.org/docs/boise_bmp_manual_DRAFT.doc.
b These discounts are applied during calculation of WQT credits; the uncertainty is subtracted from the effectiveness. Effectiveness is a measure of
the efficiency of a BMP at improving water quality by removing phosphorus.
c Range depends on scale (field, farm, or watershed).
d This BMP's effectiveness drops off after two years.
e This BMP is not recommended for calculating credit at the watershed scale; the number listed is for a farm-scale BMP.
This is the current list of BMPs, but additional BMPs may be incorporated over time or can be proposed by sources
(ISCC, 2002). At the first annual meeting in May 2001, it was decided that wetlands, individually or in combination, would
be added to the initial BMP list generated by ISCC and IDEQ (IDEQ, 2001). Ross and Associates (2000) state that
wetlands are the best "natural system" method to remove phosphorus. This BMP list was finalized during 2002 (IDEQ,
2002). The life span for BMPs eligible for trading varies depending on effectiveness and endurance.
Agricultural NPSs desiring to develop credits are encouraged to work with either the ASWCD or the CSCD, depending
on which county (Ada or Canyon) the source is located in. By working with the appropriate district, farmers develop a
conservation plan in cooperation with NRCS and ISCC. BMPs are designed as part of these conservation plans to ad-
dress water quality concerns. After the BMPs are installed and included in the plan, they can be certified as installed
according to NRCS and meeting applicable laws and regulations. Once the BMP is certified and operational, phosphorus
reduction credits can be generated and traded. Typically, within the LBR, the BMPs will operate to reduce phosphorus
during the irrigation season (April 15 through October 15); thus, credits are available for trade during this season. For-
tunately, the beneficial reduction during the irrigation season coincides with the needed phosphorus reductions required
by the SR-HC TMDL. BMPs must be inspected prior to their seasonal operation and periodically during the monitoring
period throughout the life span of the BMP.
The BMP list developed by ISCC also includes procedures for generating credits. To generate credits that can be traded
in a market, there must be an equal and beneficial reduction in phosphorus beyond the regulatory requirements of
the source. This reduction is calculated or measured in pounds of phosphorus by either of two methods. The reduced
poundage of phosphorus is then converted to credits for trading purposes.
The selection of the method used to generate the amount of phosphorus reduction depends on data availability. The
amount of phosphorus reduced by a BMP is calculated if adequate data are available or measured if data is limiting.
Calculated phosphorus reduction is the estimated average reduction with a BMP, discounted due to the potential un-
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certainty in the effectiveness of the BMP and other management factors (discussed below). Measured reductions are
quantified from grab samples taken during implementation of the BMP to quantify actual reductions, which requires an
in ow and out ow for comparison.
8.3.3 Discount Factors
The calculated reduction of phosphorus from eligible BMPs must be discounted based on the effectiveness of the BMP
and uncertainties in the effectiveness determination. These discounts are provided at the field, farm, and watershed
scale. The nutrient management BMP does not have efficiency data, but use of this BMP in combination with other
BMPs allows the other BMPs' uncertainty discounts to be reduced by 50 percent. Currently, constructed wetlands are
lacking sufficient data to determine efficiency or uncertainties and, therefore, are not recommended by ISCC for calcu-
lating credits. Consequently, use of constructed wetland BMPs requires actual measurement of phosphorus reduction
to determine credits.
To determine the actual credit given for reducing phosphorus by employing BMPs, three factors have been developed
to adjust the reduction calculation: site location, drainage delivery ratio, and river location ratio. Factors were developed
to address the net impacts at Parma of a trade between sources elsewhere in the watershed. These trades have the
potential to cause local water quality impacts in the areas where trading occurs. The localized impacts are smallest
when the BMP implementor is upstream of the PS generator because water quality is improved by the BMP before it
reaches the PS generator. However, water diversions between the trading parties may produce impacts in the river far
below the PS generator if the irrigation diversion of water containing high levels of phosphorus is returned to the river.
This would result in a net increase in phosphorus between the diversion and the returned irrigation drain.
A site location factor is included because of the transmission loss that may occur between the location where the phos-
phorus reduction takes place and the location of the discharge to a water body. To account for this transmission loss,
three site location factors were developed using common scenarios as follows:
• Site factor of 0.6 for when land runoff ows to a canal that is likely to be reused by a downstream canal user;
• Site factor of 0.8 for when land runoff does not ow directly to a drain, but through or around other fields prior to
entering drain;
• Site factor of 1.0 for when land runoff ows directly to a drain or stream through a culvert or ditch.
In addition to transmission loss between the source and the receiving water body, transmission loss can occur within
the water body. However, no data are currently available to develop local transmission models. In the absence of data,
a simpler linear calculation that represents this loss was developed. This equation is:
Drainage delivery ratio = (100 - distance in miles to the mouth of
drain from the project's point of discharge to drain) •*• 100
Distance is estimated using a CIS.
The third discount ratio, river location ratio, attempts to take into account the in uence of diversions that prevent phos-
phorus from reaching the LBR mouth. This ratio provides a means to determine equivalent loads between sources
along the LBR (Ross and Associates, 2000). Ratios are calculated and provided for each source of hydrologic input
(municipality or tributary/drain) owing into LBR.
8.3.4 Calculating Credits
Calculating credits begins with determining the amount of phosphorus produced at a location. To estimate the current
phosphorus loads from a cropland, the SISL tool is currently the most accurate and simple method to estimate soil loss
from surface-irrigated croplands. This tool is used to calculate the tons per acre of soil loss per irrigation season. The
SISL uses a baseline soil loss. ISCC established agricultural baseline loads for the project using 1996 as the base year
(IDEQ, 2001). Phosphorus reduction is compared against the phosphorus loads in 1996 because this is the baseline
used for the TMDL (ISCC, 2002). The total amount of phosphorus load is calculated by multiplying the soil loss by the
amount of acres being irrigated.
The amount of soil loss can be converted to phosphorus loads by multiplying soil loss by 2 pounds of applied phos-
phorus per ton of soil. Phosphorus loads with irrigation vary by season. Typically, more phosphorus is generated during
the beginning of the irrigation season (April 15 through October 15) due to erosion and less uptake by crop plants. The
phosphorus reduction from the calculated loads is based on the effectiveness of the BMP selected, minus the uncertainty
factor. Because NPS would also be assigned a share of the nutrient reduction under the TMDL, the nutrient reduction
generated, and available for sale, is calculated by subtracting the individual NPS share of nutrient reduction from the
total nutrient reduction created by a BMP (baseline load multiplied by the BMP effectiveness ratio. "Parma Pounds,"
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which are the unit of credit available for the trading project can then be calculated by multiplying the "saleable" the nutri-
ent reduction by the site location factor, drainage delivery ratio, and river location ratio. The concept of "Parma Pounds"
recognizes that all pounds are not equal due to water reuse within the basin. The Parma Pounds are allocated over the
months of the irrigation season to re ect the phosphorus load variability over the season. This season coincides with
the seasonal TMDL reduction requirements.
8.3.5 Example Trade
The LBR Ef uent Trading Demonstration Project conducted a trading simulation for a PS-to-NPS trade. This simula-
tion used a combination of two eligible BMPs—sediment basin and constructed wetland—installed in sequence. The
model included a conceptual design, sample permit conditions, completed forms documentation, cost estimates, and
performance evaluation (Ross and Associates, 2000).
The conceptual design for the sediment basin and wetland system consisted of running phosphorus-containing water
though the several treatment features by percent of total area (Table 8-2). Designs differ for treatment of continuous
agricultural runoff versus treatment of intermittent stormwater runoff and for phosphorus removal versus removal of other
pollutants. Conventional constructed wetland wastewater systems have tertiary treatment and polishing of municipal or
industrial ef uent. Vegetation in these wetlands helps facilitate nutrient uptake and transformation into basic elements,
compost, and plant biomass.
Table 8-2 Example Design of Sediment Basin and Wetland System
Design Feature
Sediment basin
Primary Grass filter
Vegetated wetland
Deep Water pond
Polishing filter
Percent of Total Area
3
23
23
41
10
The conceptual design took into account the maintenance requirements, such as roads for accessing portions of the
system. The wetlands depth was designed to provide for accumulation of biomass and the sediment basins could store
six years of sediment at 2 feet of depth. More than one sediment basin was provided in the design to allow for one
basin to be shut down for maintenance while the other continued to treat ows. Plants used for the design consisted of
wetland grasses like redtop (Agrostis spp.) for the primary filter, emergent plants like bulrush (Schoenoplectus spp.) for
the vegetated wetland, and herbaceous and woody species for the polishing filter. The system was designed to func-
tion with minimal ows through the operation of control gates to keep plants alive and minimize decay, which can lead
to remobilization of phosphorus. Finally, the conceptual design had inlets and outlets to allow for the measurement of
phosphorus concentrations and ows.
The performance of wetlands in removing phosphorus depends on the design, maintenance, and the concentration and
ow rate of ef uent phosphorus through the wetland. The efficiency of wetlands to remove phosphorus depends on the
ow rate. Based on mass balance models, the fraction of TP removal is approximately 90 percent at 1 cubic foot per
second (cfs) and 15 percent at 15 cfs. However, the amount of phosphorus removal in pounds increases with the ow
rate, with diminishing returns at higher ow rates (Ross and Associates, 2000). Analysis of the LBR simulated design
showed that phosphorus removal can be optimized for a site by increasing ow rates, without regards to the efficiency
of the removal process (i.e., fraction of phosphorus removed). The ability of the system to remove phosphorus was
based on the equations developed by Kadlec and Knight (1996) (Ross and Associates, 2000).
The design used in the simulation predicted phosphorus removal at a different amount for each BMP using a ow rate
of 15 cfs and concentration of 0.366 mg/L. Over a 30-year life span, the sediment basins would remove 1,040 pounds
of TP per season; the constructed wetland would remove 980 pounds of TP per season; and the combined sediment
basins and constructed wetland BMPs would remove 2,020 pounds of TP per season, or 60,600 pounds over 30 years.
This removal rate would vary within an expected SD derived from other studies. The Shop Creek facility in the Cherry
Creek Reservoir study showed an SD of 22 to 25 percent for annual average phosphorus removal. The LBR simulated
design was expected to perform better (i.e., 20 percent SD) than the Shop Creek facility because the LBR design would
not be subject to storms and increased ow variability, which reduces TP removal due to the controlled ows. A compila-
tion of data from 60 studies of 57 natural wetlands in 16 countries reported a mean SD of 27 percent for nitrogen and
an SD of 23 percent for phosphorus (Fisher and Acreman, 2004). Analysis of 44 wetlands in 17 locations throughout
the United States concluded an SD of 30 percent for phosphorus (USERA, 1999).
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The simulated design provided a detailed estimate of probable cost for the proposed system. The cost estimate was
based on a public bid process and included material, equipment, and labor in year-2000 dollars, assuming a 30-year
operation. The estimate was broken down into capital, including engineering, construction, contingency (20 percent), and
land acquisition ($10,000 per acre), and O&M. Capital and O&M were estimated at $3,004,000 and $145,800, respectively.
The cost for O&M was composed of $71,800 for annual O&M and $74,000 for harvesting wetlands plants every five
years. Using these costs and a 3 percent in ation rate, annualized cost for removal of TP was $118 per pound. If public
funds were borrowed through issued bonds, then the cost would be $161 per pound. The cost for constructing wetland
systems for treating stormwater has been estimated at $10,000 to $30,000 per acre (Zentner, 1995; Reed, 1991). This
simulation, based in year-2000 dollars, is close to $67,000 per acre. Because of the high cost of using a constructed
wetland BMP, the value of the phosphorus reduction (i.e., "Parma Pound") will need to be high to justify implementing this
BMP practice. A stringent TMDL and/or other mechanisms to partially recover costs would be necessary for use of this
BMP to be cost-effective. The high cost of using a constructed wetland BMP represented by this simulation emphasizes
the need to find lower cost engineering solutions to construction wetland design and maintenance.
A summary of the features and results of the simulated scenario that combined the sediment basin and constructed
wetland BMPs is provided in Table 8-3.
Table 8-3 Summary of Sediment Basin and Wetland System Simulation
Simulation Feature
Amount of wetland
Life span
Flow rate
Ef uent concentration
Capital cost
O&M cost
TP removed by the wetlands per irrigation season
TP removed per irrigation season
TP removed per life span
Annualized cost per pound of TP removed
Quantity
54 acres
30 years
15cfs
0.366 mg/L
$3,004,000
$145,800
980 Ibs
2,020 Ibs
60,600 Ibs
$118
Credits are generated on a monthly basis. However, the life span of a BMP varies depending on the BMP. Life spans for
BMPs provide assurance to credit buyers that credits will be available and to credit sellers that opportunities to market
their credits will persist for at least the designated life span of the BMP they choose to implement. In the LBR case study,
the life span assigned to BMPs re ected the professional judgments of scientists, regulators, and field practitioners.
Constructed wetlands were originally assigned a 5-year life span, but this was increased to 15 years based on discus-
sion within a technical focus group (Koberg, 2006). Therefore, the NPS could implement this BMP and sell credits for
15 years following the completion of the BMP, assuming maintenance and monitoring was carried out and demonstrated
effectiveness. Because the TMDL reduction goals are seasonal (May through September), the credits would only be
needed and available during these seasonal periods.
Monitoring is required to determine if a BMP is operating properly and actually reducing phosphorus. In the BMP guid-
ance, constructed wetlands require evaluation from an inspection before and during the middle of the season of use.
Consequently, during the 15 year life span of a wetland, a minimum of 30 evaluations would be necessary to continue
generating tradable credits. Monitoring is the responsibility of the NPDES permit holder who is involved in WQT The
permit holder documents the monitoring on trade tracking forms and uses this documentation to comply with his NP-
DES permit.
8.4 Summary
It is too early to determine whether the LBR Ef uent Trading Demonstration Project is a success. The framework has
been established, but no trades have occurred because of delays in providing the phosphorus reductions required by
an LBR phosphorus TMDL. The project simulation generated a scenario using a constructed wetland that could be
duplicated by sources along LBR. This simulation produced a total of 2,020 pounds of TP removal using a combination
of two BMPs: sediment basins and constructed wetlands. Theoretically, these pounds could be converted to tradable
"Parma Pounds" following discounts applied based on the location of the BMPs and trading partners. The approach the
LBR Project took towards the application of the TMDL facilitates NPS participation because they are not required to
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satisfy their assigned share of the phosphorus load reduction for their entire property before they are able to participate
in trading.
The experiences recovered from the LBR Ef uent Trading Demonstration Project highlight keys to success for a WQT
project as well as some limitations to this approach to water quality improvement. These successes and limitations can
be applied to other trading programs within the United States.
One of the fundamental components of a successful trading program is the need to have drivers for trading. These
drivers include: regulatory requirements within a defined water body, high costs for PS to reduce pollutant levels, and
the ability of NPSs or other PSs to reduce pollutants more cost-effectively than certain PSs (Kramer, 2000). It is critical
that a trading program generate sufficient publicity that sources are aware the program exists and how they can benefit
from participating. The parties involved in trades must be able to find each other and execute a meaningful agreement
or contract. Effective BMPs need to be identified, and must be practical and cost-effective to implement. The framework
for trading credits needs to be established and simple to use. This includes being able to calculate the credit, complete
required documentation, and effectively monitor and audit performance. Estimation techniques for calculating NPS
nutrient reductions must be reliable. A trading market should enable PS and NPS reductions to be achieved at a lower
cost than the individual PSs could accomplish within their own operations (ISCC, 2002; Kramer, 2000). Additionally,
there are spatial components to a successful trading program. This geographic issue consists of the need for a larger
number of PSs and NPSs within the drainage basin requiring nutrient reductions (Kramer, 2000). There must be en-
forcement and penalties for non-compliance to ensure that BMPs are installed and performing as expected and trades
are occurring equitably. Finally, the trading approach must result in a reduction in pollutants that is measurable and
meets the objectives of the TMDL.
There are several limitations or challenges to a successful WQT program. Trading could be hampered by the lack of an
established or known trading framework. Additionally, trading would fail to be effective if it is viewed as, or in practice
actually is, too cumbersome fortraders to use or regulators to evaluate. Similarly, transaction costs must be minimized to
ensure utility of the program (Kramer, 2000). Trading needs to avoid hot spots or localized areas in a watershed with high
levels of nutrients (Kieser and Fang, 2005); otherwise, the local water loads could become worse instead of improving.
Ultimately, WQT is unsuccessful if it fails to create environmentally equivalent nutrient reductions. Equivalency can be
difficult to demonstrate or calculate when there are uctuations in phosphorus generation within a given timeframe. For
example, irrigation produces more phosphorus earlier in the irrigation season due to erosion and less uptake by crops
(ISCC, 2002). This variability may not necessarily coincide with variable or constant phosphorus loading by PSs.
Obstacles to developing the trading program include incurring high expenses and intensive use of resources to develop
the trading framework. Furthermore, the irrigation districts (PSs) and farmers (NPSs) in the LBR demonstration project
were leery about losing water rights by participating in a program. NPSs are also wary that their participation in generating
credits by reducing phosphorus loads might encourage or facilitate their being subjected to regulations, requiring them
to reduce their phosphorus loads to the LBR (King, 2005; Environomics, 1999). Currently, NPSs are not regulated and
trading is voluntary. Public comments by environmental interest groups on pollutant trading expressed concerns about
the ability to hold PSs fully accountable for trades, the verifiability of NPS trades, and the need to obtain trade-by-trade
regulatory approval. The participants in the demonstration project felt that the LBR framework established highly effec-
tive and locally tailored solutions to CWA liabilities.
The LBR Ef uent Trading Demonstration Project identified several additional data and investigational needs of trading
programs and use of constructed wetlands as BMPs to remove phosphorus. For example, the forms used for documenting
trading activity generated in a trading program need to conform to the Paper Reduction Act. A simple but formal audit
plan is necessary for a trade tracking system. In the LBR case study, there were no deadlines by which a trade must
be completed in order for it to be included in a given month's monitoring report. This relationship needs to be explicit.
The support for discounts developed to generate credits is incomplete. For example, the transmission losses and the
fate and transport of nutrient uptake capacity between the trading partners need additional study to refine discounts.
Further watershed analysis on the effects of diversion on localized water quality impacts could strengthen the discount
relationships. Additionally, more evaluation is needed on the use of "total mass" caps for PSs to prevent localized im-
pacts. These analyses could be part of ongoing review and evaluation of an operating program, this would distribute
the study and analysis costs over a period of years and would leverage the additional BMP monitoring and verification
requirements required to validate credits.
The ISCC determined there is insufficient data for deriving efficiency or uncertainty values for calculating phosphorus
removal of constructed wetlands. Consequently, phosphorus reduction from constructed wetlands must be measured,
which requires incorporation of in ow and out ow structures in wetland design, which creates a design limitation for the
use of constructed wetland BMPs. Wetland design, including the way water ows into and out of a wetland, is critical
to the effectiveness of a constructed wetland at removing phosphorus. For example, ow delivery or departure could
be by sheet ow or infiltration, which makes measuring phosphorus content more difficult. The variability in designs and
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their ability to remove phosphorus from PSs or NPSs needs additional investigation. Through this investigation, various
scenarios and calculated credits could be generated to guide sources in the selection of this BMP.
Another area needing investigation is the appropriate life span assigned to BMPs. In the LBR BMP list, the life span for
a constructed wetland BMP is 15 years based on a technical focus group decision among participants during develop-
ment of the WQT project (Koberg, 2006). However, the example simulation used a 30-year BMP life span. Due to the
high cost of constructing a wetland for phosphorus treatment, it is more cost-effective for these BMPs to be used for
trading programs for as long as they are functional. This would be similar for any BMP that is maintained and performs
phosphorus removal. Adjustments in the life span of BMPs or a discount for the age of the BMP should be considered
as a part of WQT program review and evaluation. This would avoid the necessity of making long-range assumptions
during the initial stage of program implementation.
Finally, information and planning are lacking on the long-term fate of phosphorus removed using BMPs such as con-
structed wetlands. If sediment or plants are harvested containing large concentrations of phosphorus, the ultimate
disposition of this harvested material may only transfer the environmental problem to another location or medium, such
as groundwater used for drinking water.
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9.0 Case Study -Tar-Pamlico River and Neuse River, North Carolina
The Tar-Pamlico and Neuse rivers ow parallel to each other approximately 50 miles apart and empty into the Pamlico
Sound, an estuary in which the circulation of water is slowed by a string of islands between it and the Atlantic Ocean.
In the mid-1980s, fish kills and algal blooms in the Tar-Pamlico and Neuse River Estuaries due to eutrophication cre-
ated public concern regarding water quality. Subsequently, the NCEMC declared the upper portion of the Neuse River
Basin NSW in 1983, the entire Neuse River Basin NSW in 1988, and the entire Tar-Pamlico Basin NSW in 1989. In
addition, each river basin was added to the state's 303(d) list for chlorophyll a (USEPA, 2005b). As required by North
Carolina state law, the NSW designation initiated a process to develop and implement nutrient management strategies
for each river basin.
The strategies developed over the next decade included measures to address both PSs and NPSs of nutrients, in-
cluding WQT programs. The trading model for both these programs can best be described as an exceedance tax or a
group cap-and-trade program. PSs are assigned a baseline maximum nutrient load and nutrient reduction goals, which
cumulatively set the overall nutrient loading goals for the water body. PS entities are provided the option to form an as-
sociation so that they are able to collaborate to meet those goals. In the event that the collective exceeds the nutrient
limits, each program developed a nutrient offset fee for each additional pound of nutrient discharged that is paid to a
state-administered fund for implementing BMPs to reduce the nutrient load from NPSs.
In this case study, the Tar-Pamlico Nutrient Reduction Trading Program and the Neuse River Basin Sensitive Waters
Management Strategy are described in separate sections and then compared.
Figure 9-1 Watersheds in North Carolina.
9.1 Tar-Pamlico Nutrient Reduction Trading Program
The Tar-Pamlico Nutrient Reduction Trading Program was initiated in 1990. During Phase I (1990-1994) of the program,
the Association was assigned an interim cap for combined discharges, which required a 44,092-lb/yr reduction in TN
and phosphorus (Kerr et a/., 2000), and a 20 percent reduction in nutrients over five years. In addition, the Association
was tasked with the following: (1) develop an estuarine model; (2) perform an optimization study for capital improve-
ments to WWTPs; (3) fund the initial design and administration of the WQT program ($150,000 was provided over a
two-year period); (4) make minimum payments into the offset fund if cap was not exceeded (these payments amounted
to $850,000 at the end of Phase I); and (5) perform water quality monitoring to document compliance with the cap
(Breetz et a/., 2004; Kerr et a/., 2000). The offset fee was set at $25.40 per pound, and credits expire after 10 years.
The fees are paid to the North Carolina Agriculture Cost Share Program, administered by the DSWC, a pre-existing
program that funds 75 percent of the capital costs associated with voluntary implementation of agricultural BMPs.
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Throughout Phase I, the association was able to meet the nutrient reduction goals collectively through improvements
in operational efficiencies.
During Phase II (1995 through 2004), the focus of the nutrient management strategy shifted to include NPSs based
on the recognition that NPSs contribute the majority of nutrient loading to the watershed. The modeling completed by
the Association in Phase I estimated that NPSs accounted for 92 percent of the nutrient loads (Gannon, 2005b). A
goal of 30 percent reduction was set for both PSs and NPSs and the limit for discharge of phosphorus was set at 1991
levels. An interim target of 60 percent progress towards these goals by 1999 was set. If progress was inadequate, the
NCDWQ and NCEMC would evaluate whether additional regulatory requirements were necessary (Kerr et al., 2000).
When adequate progress had not been made, mandated rules on riparian buffers, fertilizer application, stormwater,
and agriculture were adopted by the NCEMC and went into effect in 2000 and 2001 (Gannon, 2005b). The Phase II
agreement reduced the price of NPS credits to $13 per pound. Throughout Phase II, the Association has maintained
discharges well below the caps assigned without needing NPS offsets (Breetz et al., 2004).
The Phase III agreement spans an additional 10 years (2005 through 2014), with an amendment after 2 years to ad-
dress potential needs for improvements. The Phase III Agreement updates Association membership and maintains the
nutrient caps established in Phase II. It also proposes actions over the first two years that will improve the offset rate,
resolve related temporal issues (life span of offset credits), and evaluate alternative offset options. The offset credit life
span, what happens after 10 years when the credits expire, and how to handle credits that have been banked by the
Association, but not used within 10 years, are issues that participants in the Phase III agreement are currently working
to resolve (Huisman, 2006). It also establishes 10-year estuary performance objectives and alternative management
options. If water quality in the estuary worsens by 2008, a process to re-model the estuary and revise TMDLs will be
initiated (Gannon, 2005b).
9.1.1 Background
The Tar-Pamlico River Basin is located north of Neuse River Basin and encompasses 5,400 square miles (Figure 9-2).
When the NCEMC designated the Tar-Pamlico basin NSW in 1989, the DENR developed an initial management strategy,
as required by state law, which focused reductions of nutrients in the discharges from PSs. The Water Quality Control
Commission proposed discharge limits of 2 mg/L TP and 6 mg/L TN (4 mg/L TN in summer and 8 mg/L TN in winter);
total nutrient (e.g., tons of TN) load reductions were not specified. It was estimated that to meet these standards, it would
cost PSs between $50 and $100 million in capital costs for technology upgrades. PSs opposed the strategy due to the
costs and because they believed that discharges from NPSs were also responsible for eutrophication. Environmental
groups also opposed the strategy because of the lack of a strategy for NPS reductions and the lack of a goal for PS
reductions. Phase I of the NSW implementation strategy, which includes the WQT program, was adopted in December
1989 and was the result of a cooperative stakeholder process with the Association, the state, and the North Carolina
Environmental Defense Fund (NCEDF) (Kerr ef al., 2000).
Partners involved in the effort were NCDWQ, Soil and Water Conservation Districts, North Carolina DSWC, North
Carolina Cooperative Extension, USDA's NRCS, North Carolina Department of Agriculture, North Carolina Farm Bu-
reau, North Carolina State University, the Association, the agricultural community, and commodity groups. Fourteen
dischargers equaling about 90 percent of all PS ows to the river joined the Association (Gannon, 2005b). The NCEMC
brought together stakeholder groups of affected parties and provided the participants with a chance to express differing
viewpoints. Stakeholders involved in the process included environmental groups, municipalities, developers, businesses,
and the public (USERA, 2005c).
A TMDL for nitrogen and phosphorus was developed late in Phase I, assisted by the estuarine modeling initiative
conducted as a part of the Phase I agreement, and approved in 1995 (Environomics, 1999). The model predicted that
a 45 percent reduction would be necessary to meet in-stream water quality goals; however, due to the uncertainty as-
sociated with the modeling, a 30 percent reduction in nitrogen loading for all sources was established by the Phase II
agreement (Kerr et al., 2000). The trading program is one element of the implementation strategy of the Tar-Pamlico nutri-
ent TMDL; as previously described, it also charged NPSs with a 30 percent reduction. The environmental organizations
Environmental Defense and Pamlico-Tar River Foundation (PTRF) were participants in the Phase I and III agreements
(Gannon, 2005b). However; they chose to not participate in the Phase II agreement because they disagreed with the
30 percent reduction goal that was established.
Phase III of the NSW implementation strategy was adopted as a continuation and update of the Phase II strategy with
specific goals to improve and refine the program.
Two years into the implementation of the Phase II agreement, regulations modeled after the Neuse nutrient reduction
regulation were developed in conjunction with stakeholder consultation (Gannon, 2005b). These regulations include:
buffer protection rules (15A North Carolina Administrative Code [NCAC] 2B.0259, .0260 and .0261); nutrient manage-
ment rule (15A NCAC 2B.0257); stormwater rule (15A NCAC 2B.0258); and agriculture rules (15A NCAC 2B.0255 and
.0256) (NCDWQ, 2005).
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Stream
I | State Boundary
Freeway
Pamlico Watershed
Figure 9-2 Tar-Pamlico River Basin.
The trading program was designed so that fees for offset credits would be paid to the NC Agriculture Cost Share Program.
The NC Agriculture Cost Share Program is responsible for allocating those funds to the Tar-Pamlico Basin, targeting
projects geographically for the most cost-effective nutrient reductions to the estuary. Once PSs have purchased credits,
they are no longer liable for ensuring NPS BMPs are implemented and successful. The state assumes responsibility
for the monitoring and verification of BMPs. The DSWC has final authority over BMP implementation and the NCDWQ
has final authority over nutrient tradeoffs and allocations (Breetz et al., 2004). The primary focus of the Agriculture
Cost Share Program is to provide farmers with assistance implementing agricultural BMPs aimed at reducing nutrients
(Research Triangle Institute & USERA, undated).
9.1.2 Program Performance
The Tar-Pamlico Nutrient Trading Program has been part of a successful strategy to reduce nutrients in the Tar-Pamlico
Basin although, to date, no trades have occurred. Thanks to the exibility of the collective discharge goals afforded the
Association, members of the Association have been able to improve treatment efficiencies and time technology upgrades
with planned expansions so that improvements in treatment efficiency are cost-effective (Allen and Taylor, 2000). As
opportunities for cost-effective technology upgrades are exhausted, trading will likely occur in the future.
The Association also provided up-front funding of almost $1 million worth of agricultural BMPs, in large part through a
federal USERA grant, and have been able to bank the credits toward future cap exceedances (Gannon, 2005b).
By the end of Phase II, the Association successfully met the nutrient reduction goals and by 2003 had decreased nitro-
gen and phosphorus discharges by 45 percent and 60 percent, respectively, even though ows increased by 30 percent.
The agriculture community was also successful in meeting its nutrient reduction goals; it collectively reduced nitrogen
discharges by 45 percent by 2003 (Gannon, 2005b), as estimated by land-based accounting methods that estimate TN
and TP percentage reduction with implementation of BMPs. The land-based accounting methods are discussed further
in Section 9.1.3.2.
As a result of watershed-wide efforts, impaired acreage in the estuary has been reduced by 90 percent (from 36,200
to 3,450 acres) (Gannon, 2005a), and one segment of the Pamlico estuary has been removed from the 303(d) list for
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chlorophyll a (USEPA, 2005b). Trends in nutrient loading in the Tar-Pamlico Basin from 1991 to 2002 were evaluated
using the Seasonal Kendall test, a nonparametric trend test that is a generalization of the Mann-Kendall test (Kennedy,
2003). The results indicate significant, negative trends in ow-adjusted concentrations for both TP and TN. Over the
selected study period of 1991 through 2002, the estimated decreases in TP and TN concentration over the 12 years
are 0.046 mg/L and 0.203 mg/L, respectively. This represents a reduction ofTP and TN through 2002 of 33 percent and
18 percent, respectively (see Figure 9-3 and Figure 9-4) (Kennedy, 2003).
Grimesland
SEASONAL KENDALL (SKWC)
Slope = -0.01686
2xP = 0.0197
Signif95%
90 91 92 93 94 95 96 97 98 99 100 101 102 103
Figure 9-3 Estimated TN concentration decrease using Seasonal Kendall test.
Grimesland
» ALL SEASONS
^— Seasonal Sen Slope
SEASONAL KENDALL (SKWC)
Slope = -0.00378
2xP = 0.0006
Signif99%
92 93 94 95 96 97 98 99 100 101 102 103
YEAR
Figure 9-4 Estimated TP concentration decrease using Seasonal Kendall test.
A key factor that hampered the progress of NPS nutrient reduction activities during the early part of Phase II was lim-
ited funding/lack of resources to facilitate accounting for progress on NPS BMP implementation (NCDWQ, 1999). In
addition, unknowns associated with atmospheric deposition of nitrogen make it difficult to address this source of NPS
nutrients (Gannon, 2005b).
9.1.3 Technical Performance
The NSW implementation strategy established a fixed fee per pound of TN discharged above the discharge limit. A
nutrient source budget (an accounting of all nutrient sources in the watershed) was prepared for the Tar-Pamlico basin
in 1986 and revised in 1988 to re ect significant changes in the watershed. The researchers who developed the budget
determined that nitrogen was likely the limiting factor in plant growth. There were uncertainties in the estimates, but with
ongoing development in the basin it was crucial that initial goals be established. The NCDWQ projected the 1994 ow
for all the Association members at 30.55 mgd. Assuming no nutrient reductions from pre-strategy conditions, NCDWQ
estimated that total nutrient loading in 1994 would reach 1,278,000 Ib/yr. Under the original NSW proposal, which re-
quired mandatory phosphorus and nitrogen limits for PSs, projected loadings for 1994 would decrease to an estimated
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936,965 Ib/yr, a reduction of 440,924 Ib/yr. Subsequently, NCDWQ, the Association, NCEDF, and the PTRF together
established 440,924 Ib/yr as the nutrient reduction goal for Phase I of the WQT program. Of this, 396,832 Ib/yr is for
nitrogen and 44,092 Ib/yr is for phosphorus (Research Triangle Institute & USEPA, undated).
9.7.3.7 Methods for Defining Caps and Measuring Baseline Nutrient Loading
During Phase I, HydroQual developed a two-dimensional, laterally averaged hydrodynamic water quality model to
predict the impacts of nutrient loading in the estuary. The model extends from Greenville to Pamlico Point, a distance
of approximately 60 miles. 1991 was chosen as the calibration year for the model because it represented when typical
impairment of the estuary was evident. It was also the baseline year when PSs in the Association were required to
perform nutrient monitoring (Gannon, 2005b).
A water quality station near the town of Washington was chosen as the point at which management strategies would be
evaluated because modeling results indicated that this was where the greatest number of chlorophyll a and dissolved
oxygen violations occur, and the magnitude of the violations was the greatest. Thus, it is the critical portion of the river
(Gannon, 2005b).
TMDL targets were set in Phase II at 2,778,000 Ib/yr of TN and 397,000 Ib/yr of TP at Greenville based on the relatively
low ow year 1991. Given that Washington is downstream and additional loading would occur between those points, TN
load delivered to Washington was calculated to be 4,280,000 Ib/yr. Therefore, the 30 percent TN reductions goal for all
sources was set at 1,285,000 Ib/yr (Gannon, 2005b). PSs were allocated 8 percent of the total nutrient load reductions,
and NPSs 92 percent. For Phase III, these load reductions translate to a cap of 891,271 Ib/yr for TN and 161,070 Ib/yr
forTP for PSs (Gannon, 2005b), and a cap of 2,109,220 Ib/yr TN and approximately 1,851,883 Ib/yr TP for NPSs.
The modeling results predicted that a 30 percent reduction in TN would significantly reduce the frequency and severity
of algal blooms in the estuary. To prevent exceedances of the chlorophyll a standard of 40 ug/L, the model predicted that
a 45 percent reduction in TN would be needed. However, given that the level of uncertainty in the modeling increases
the further conditions are from baseline conditions, 30 percent was selected at the target for reducing TN. There were
plans to recalibrate the model to lower nutrient loading conditions after 30 percent reductions were achieved in order
to more accurately determine whether additional reductions are needed. However, recalibration has been postponed
pending the results of other estuary evaluations (Gannon, 2005b).
9.7.3.2 Methods for Quantifying Nutrient Load Reductions
Point Sources. Assessing compliance of PSs within the trading program is relatively simple. Since July 1991, Association
facilities have been performing weekly ef uent monitoring forTP, TN, and ow. The Association reports monitoring data
to NCDWQ annually. NCDWQ has developed a set of guidelines for estimating ow and concentration if this information
is not provided. Water quality monitoring is performed according to monitoring protocols defined or referenced in their
NPDES permits (Gannon, 2005b).
Nonpoint Sources. Although wetlands have not been a primary method used to reduce nutrient loads, the methodolo-
gies developed for assessing the progress of NPSs towards nutrient reduction goals are applicable to assessing the
effectiveness of constructed and restored wetlands as NPS BMPs. This is relevant to a general discussion of how to
account for the reductions in NPS nutrients. The NCDWQ determined that measuring compliance with instream loading
targets would have required a combination of complex modeling of processes occurring between edge of manage-
ment unit (e.g., a given property or unit area of land bordering a body of water) and the water column instream (which
would have significant uncertainty), and a substantial amount of quantitative water quality monitoring to support that
modeling (Gannon, 2005b). As a result, they have developed methods to assess compliance with load reduction targets
based on land-based accounting methods that estimate nitrogen and phosphorus percentage reduction based on BMP
implementation.
The NCDWQ has developed estimates of nutrient removal efficiencies based on "model local stormwater programs"
developed under the Neuse and Tar-Pamlico stormwater rules and agency research. Table 9-1 is the latest table devel-
oped by NCDWQ of typical nutrient removal efficiencies. It is being used to calculate NPS nutrient reductions for both
of these programs (Bennett and Gannon, 2004).
Two other tools have been developed; the Nitrogen Loss Evaluation Worksheet (NLEW) and the Phosphorus Loss
Assessment Tool (PLAT). Both tools were developed for nitrogen and phosphorus accounting under the Tar-Pamlico
agriculture rule. The NLEW was developed by a multi-agency task force to meet the need for a scientifically valid ni-
trogen loss accountability method for use in the Neuse and Tar-Pamlico nutrient strategies. It is an empirically-derived
spreadsheet model that estimates nitrogen export from agricultural management units. It was developed to estimate
relative reduction in nitrogen export through a pre- and post-BMP implementation calculation, rather than estimating
delivery to surface waters (Gannon, 2003). The NLEW uses crop and soil acreages, fertilization rates, and areas of BMP
implementation to estimate nutrient uxes from agricultural land.To estimate BMP implementation before implementation
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of the Agriculture Rule, the Local and Basin Committees (LAC)23 used cost-share records, if they existed, and relied on
best professional judgment where unassisted BMP implementation was significant (Gannon, 2003).
Table 9-1 New Nutrient Removal Efficiencies for Stormwater BMPs Used Under the Neuse and Tar-Pamlico Storm-
water Rules
Practice
Wet pond
Stormwater wetland
Sand filter
Bioretention
Grass swale
Vegetated filter strip with level spreader
50-foot restored riparian buffer with level spreader
Dry detention
TN efficiency (%)
25
40
35
35
20
20
30
10
TP efficiency (%)
40
35
45
45
20
35
30
10
From Bennett and Gannon (2004).
9.1.4 Economic Performance
9.1.4.1 Calculating Offset Credit Value
When the Phase I agreement was developed, the estimated cost of achieving the 440,925 Ib/yr nutrient reduction goal
using agricultural BMPs alone was $11.8 million: $10 million on the ground and $1.8 million in administration. These
values were determined by multiplying the reductions by a factor of $25.40 per Ib/yr, the estimated cost for removing
1 pound of nutrient per year using BMPs. The rate was drawn from BMP funding experience in the adjoining Chowan
River basin. The calculation of the cost factor included a margin of safety by multiplying by a factor of three for cropland
BMPs and by a factor of two for animal BMPs (Research Triangle Institute & USERA, undated).
The offset fee was refined when the Phase II agreement was developed. The base offset fee takes into account farm-
ers' capital costs, maintenance costs, BMP effectiveness, area affected, and BMP life expectancy. BMP effectiveness
values were based on a literature review that included empirical studies of conservation tillage, terracing, and buffer strip
BMPs in the Chesapeake Bay. The fee also includes a trading ratio that re ects a 10 percent increase for administrative
costs and a 200 percent margin of safety. Credits for structural BMPs have a useful life of 10 years, while non-structural
BMPs have a credit life of 3 years (Breetz et a/., 2004; Gannon, 2005b). The type of BMP eligible for generating nutri-
ent reduction credits was left broad: any BMP included within the NC Agriculture Cost Program that is associated with
nutrient reduction can be used to generate credits (Huisman, 2006). The key limitation is that nutrient reductions from
BMP projects designed to satisfy the 30 percent TN reduction required of all agricultural operations cannot also be used
to generate nutrient offset credits.
The following equation illustrates how the offset fee was calculated.
2($5.90/lb N) + 0.1[2($5.90/lb N)] = $13/lb N
Where 2 accounts for uncertainty in BMP effectiveness, $5.90/lb N high-end cost effectiveness for nitrogen
removing BMPs, and 0.1 adds in administration costs (Gannon, 2005a).
The offset payments made by the Association to the Agriculture Cost Share Program are used to fund voluntary BMP
implementation (75 percent state/25 percent producer) and pay for staff resources to track and target contracts and
verify compliance.
The NCDWQ plans to work to refine the offset credit calculations further during the first two years of Phase III, and
NCDWQ plans to work in consultation with signatories to the Phase II agreement to develop improvements to the offset
rate that address the following issues:
• Develop an offset rate for exceedances of the phosphorus cap.
• Update cost-effectiveness data developed in the 1995 RTI report.
• Add current BMPs not addressed in the 1995 RTI report.
23 LACs were established as a part of the agriculture rules to develop plans for meeting the 30 percent reduction goal, and pro-
vide technical assistance to farmers reporting on progress to the EMC.
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• Project BMP implementation for the foreseeable future, including relative numbers and geographic distribution if
possible.
• Include uncertainty estimates with all cost effectiveness values.
• Replace the current value with single nitrogen and phosphorus values weighted for projected BMP implementation.
Include spatial weighting if possible to account for differences in estuary delivery due to BMP distribution within the
basin. Evaluate the use of uncertainty bounds to replace the current safety factor.
• Revisit the administrative cost factor.
• Resolve understanding on payment longevity and credit life initiation (Gannon, 2005b).
As a part of this work, NCDWQ determined the cost-effectiveness of implementing various BMPs in reducing nutrient
loads (Table 9-2).
Table 9-2 Nitrogen Removal Cost-Effectiveness Comparison
Practice
Agriculture
• Water control structure
• Nutrient management
• Vegetated filter strip
• Conservation tillage
Stormwater/bioretention
Riparian wetland restoration
$ per Pound
(30-year life equivalent)
$1.20
$7- $9
$7- $8
$20 - $80
$57 - $86
$11 -$20
Source: Gannon, 2005a.
9.1.4.2 Program Costs
The trading program has yielded substantial savings forthe Association, which originally estimated costs fortechnology
upgrades at $50 - 100 million, although a revised estimate of costs to the Association without trading puts potential
costs at $7 million to achieve a comparable level of nutrient reduction that a $1 million investment in NPS controls
yielded (DeAlessi, 2003).
According to the USERA Office of Water (2005), in addition to costs to the Association, the overall costs of the NSW
implementation strategy24 have been as follows:
• The North Carolina Agriculture Cost Share Program, administered by the DSWC, contributed $12.5 million between
1992 and 2003.
• Another DSWC-administered program, the federal Conservation Reserve Enhancement Program, has obligated
approximately $33.1 million in the Tar-Pamlico River Basin since 1998.
• Between 1995 and 2003, approximately $2.67 million in CWA section 319 expenditures supported a variety of NPS
projects in the Tar-Pamlico Basin, including BMP demonstration and implementation, technical assistance and
education, CIS mapping, development and dissemination of accounting tools, and monitoring.
9.1.5 Administrative Performance
PSs and NPSs are required to achieve environmental goals and provide sufficient information to document compliance.
The NCEMC, NCDWQ, and Soil and Water are the key administrative bodies for the NSW management strategy. The
government agencies retain the ability to take enforcement actions against PSs and NPSs in the event that they are
not able to demonstrate compliance.
9.7.5.1 Point Source Accountability
The Agreement signed by the Association, NCEMC, NCDWQ, and Soil and Water is the primary mechanism used to
assure accountability. The NPDES permits of the Association members do not contain limits for nitrogen, which means
that if they overperform, they are not subject to the antibacksliding requirements in the federal CWA (which would result
24 The trading program is just one part of the overall strategy developed for the Basin.
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in adjustments in permit limits if association members showed they could meet more stringent requirements).25 This
would effectively penalize environmental performance. The NPDES permits do, however contain a "reopener" clause
stating that if conditions in the agreement are violated, then permits would be revised to impose new discharge limits
(Kerr et a/., 2000). The Association documents its nitrogen loading for the year in an annual report (Gannon, 2005b).
Non-Association members (the remaining 10 percent of the PS dischargers) are subject to slightly different rules. They
are regulated by traditional PS permitting requirements. In addition, they are required to offset new nutrient loading by
funding BMPs at an offset ratio of 1.1:1 (Kerr et a/., 2000).
9.7.5.2 Nonpoint Source Accountability
The performance of NPSs on nutrient reduction goals is tracked using three methods: tracking activities, computer
modeling, and sampling.
Tracking Activities. The NCDWQ and EMS use annual reports submitted by LACs to verify progress of NPSs on BMP
implementation plans developed by LACs. LACs were created to develop agriculture BMP implementation strategies.
LACs are required to submit annual reports on progress (Gannon, 2005a).
Modeling. Computer modeling efforts have included improving the Tar-Pamlico Estuarine Water Quality Model used to
develop the basin-wide strategy. In addition to the NLEW and PLAT modeling tools developed for agriculture, an Excel-
based model was developed to calculate nitrogen and phosphorus loading associated with stormwater runoff from new
developments before and after BMP implementation (Gannon, 2005a).
Monitoring. The Soil and Water Conservation Districts perform compliance monitoring on BMP implementation; they
inspect 5 percent of all contracts for cost share projects per year and all animal waste systems twice per year; and
review all local programs every five years (Gannon, 2005a). The NLEW is also used to track progress.
9.2 Neuse River Basin Nutrient Sensitive Waters Management Strategy
The 1997 Neuse River Basin NSW Management Strategy (Neuse NSW Strategy) established nitrogen allocations and
control options to improve water quality in the Neuse River Basin. The strategy included elements of PS-NPS trading
for nitrogen allocations and PS-NPS offsets for nitrogen loading (Breetz et a/., 2004). It set a 30 percent TN reduction
target for all sources (including PSs and NPSs) that would need to be achieved within five years, by 2003 (15A NCAC
2B.0234). The strategy also established a group compliance option, which PS dischargers over 5.0 mgd have the op-
tion to join. In 2004, the NRCA included 22 members. It issued a single, collective NPDES permit for nitrogen based on
the sum of the members' individual nitrogen allocations. PS-PS transactions for nitrogen allocations can occur either
internally within the NRCA or between members of the NRCA and non-members (Breetz et a/., 2004).
The system established for PS-NPS trades is similar to that of the Tar-Pamlico Nutrient Reduction Program and can best
be described as an exceedance tax, rather than a traditional trading program. Potential trading parties include: members
of the NRCA, any discharger holding an allocation, and landowners. Trades with NPSs are conducted indirectly through
the North Carolina Wetlands Restoration Fund. Landowners receiving grants from the Wetlands Restoration Fund are
indirect trading partners. As with the Tar-Pamlico Program, responsibility rests with the state for ensuring nutrient offset
projects are implemented and successful (Breetz et a/., 2004).
A fixed, per-pound price has been established forthe purchase of TN offset credits. Credits may be purchased if new or
expanding dischargers cannot secure nitrogen allocations from other PSs or if the NRCA exceeds its annual nitrogen
allocation. In addition to the offset payments, the NRCA is subject to penalties and other enforcement action for any
exceedance. In that event, the NRCA members are also subject to enforcement if they exceed their individual allocations
as listed in the NRCA's permit. Non-members with TN limits are not required to make offset payments, but are subject
to enforcement for any exceedance of their TN limits (15A NCAC 2B.0234) (Breetz et a/., 2004).
The Neuse NSW Strategy also created a mechanism for NPS-NPS trades. The Neuse NSW Stormwater Requirements
(15A NCAC 2B.0235) set a nitrogen export standard for local governments identified within the regulation based on
population and growth rate. Local governments subject to this regulation are required to develop stormwater management
program plans and have them approved by the NCEMC. Local governments that do not submit stormwater management
program plans or fail to implement them will be subject to NPDES permitting requirements. The plans are tailored to
help the local government ensure nutrient reduction goals are met. A key component of the plans is review and approval
of stormwater management plans of new developments to ensure they will comply with a nitrogen export standard of
3.6 pounds per acre per year. Developers have the option of installing stormwater BMPs to satisfy this standard or may
25 The USEPA Water Quality Trading Policy (2003) has since addressed this issue directly, stating, "ant/backsliding provisions
will also generally be satisfied where a point source generates pollution reduction credits., .and it later decides to discontinue
generating credits, provided that the total pollutant load to the receiving water is not increased, or is otherwise consistent with
state or tribal antidegradation policy."
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choose to implement stormwater BMPs that will attain maximum allowable nitrogen export rates and purchase offsets
for the remainder of the nitrogen export rate above the rate set for local governments.
An initial focus on education is another aspect of Neuse NSW Strategy that is different than the Tar-Pamlico Program.
At the outset of the 1997 strategy, the Neuse River Education Team (NRET) was created (and funded) with a mandate
to educate NPSs of nutrients (agricultural producers, homeowners, and cities) (Newport, 2004).
9.2.1 Background
The Neuse River Basin is located directly to the south of the Tar-Pamlico River Basin and covers 6,192 square miles
(Figure 9-5).
It was not until 1997 that a WQT program was included in the Neuse River Basin NSW Management Strategy. When
the NCEMC developed the original Nutrient Management Strategy (Neuse NSW Strategy) for the Neuse River Basin
in 1988, most of the nutrient problems in the lower Neuse region were occurring in the lower freshwater portion of
the river near Street's Ferry, and phosphorus was considered the most important nutrient (NCDENR, 1998); thus the
focus of the Strategy was on reducing TP The strategy gave PS dischargers with ows greater than 0.5 mgd and all
new facilities a TP limit of 2.0 mg/L. Specific goals were not established forTN, although the NCDWQ also stated that
nitrogen loading from NPSs should be controlled. The Agricultural Cost Share Program was identified as the primary
mechanism for reducing nitrogen from NPSs.
The first Basin Wide Plan for the Neuse River was developed in 1993. At this point, TN was becoming a concern in
the Neuse because monitoring and modeling in the Tar-Pamlico Basin were showing that nitrogen appeared to be
the more important nutrient for brackish estuarine waters. The plan recommended that the Neuse NSW Strategy be
reevaluated before it was updated in 1998 (NCDENR, 1998). Major fish kills in 1995 provided further impetus to revise
and update nutrient controls. In 1997, the Neuse NSW Strategy was updated by the NCDWQ. It focused on nitrogen
and established the Neuse NSW Rules, which were crafted to meet and maintain a 30 percent nitrogen reduction goal
within five years, and retained the technology-based concentration limits forTP. Nutrient impacts also led to listing the
basin on the 303(d) list and to the development of TMDLs, which USEPA Region 4 approved in 2001 (USERA, 2002b
and Environomics, 1999).
Legend
Stream
Freeway
I | Slate Boundary
Meuse Watershed
_A
Shaw
CLIENT NAME
CLENT LOCATION
FIGURE 9-5
Neuse River Basin
Figure 9-5 Neuse River Basin.
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The Neuse NSW Rules (Rules .0232, .0234, and .0240 of 15A NCAC 2B) were developed by the state in an effort to
address the major known sources of nutrients in a exible, fair, and reasonable fashion (NCDENR, 1998). PSs were
estimated to contribute approximately 24 percent of the nitrogen and phosphorus loading to the estuary (Brookhart,
2003, Gannon, 2006). There were 111 dischargers in 1995 (the baseline year); it was estimated the largest 32 discharg-
ers accounted for over 95 percent of the TP loading from PSs to the estuary (Breetz et al., 2004). Thus, more than 600
people participated in the public hearing process. The group compliance option came about as a result of suggestions
from PSs. They were concerned that stringent nutrient allocations would have been burdensomely expensive, and they
were interested in more cost-effective and exible regulatory structures (Breetz et al., 2004). The Tar-Pamlico Nutrient
Trading Program, which had entered into Phase II at that point, was used as a template for the Neuse Trading Program.
The draft rules were brought to the public for comment before being adopted in December 1997.
According to Breetz et al. (2004), participants in the Neuse NSW Implementation Strategy include the following orga-
nizations:
• NCDWQ: issues NPDES permits to individual dischargers and a group NPDES permit to the NRCA; provides regu-
latory oversight for the group nitrogen allocation.
• NCEMC: responsible for developing and adopting the Neuse River Nutrient Management Strategies and associ-
ated rules.
• NRCA: association of PS dischargers, primarily large municipal WWTPs, with a common nutrient cap.
• Lower Neuse Basin Association (LNBA): a nonprofit coalition of dischargers that conducts instream monitoring;
preceded the NRCA by several years and served as the starting point for the development of the NRCA. Many
LNBA members became NRCA members.
• Wetlands Restoration Fund (administered by the Ecosystem Enhancement Program [EEP]).
• USEPA, Region IV.
• Neuse River Foundation and Neuse Riverkeepers: environmental advocates.
NCDWQ oversees compliance with the group nitrogen cap. The NRCA manages the individual nitrogen discharge of
members through an internal fee system.
The NRCA has been successful at meeting the nutrient discharge limits and has not needed to purchase any offsets.
However, approximately $5 million in offset fees has been collected from Neuse stormwater projects (Gannon, 2005a).
Payments to the Wetlands Restoration Fund are allocated to wetland construction and restoration projects. There are
currently numerous projects in design; most are constructed wetlands (Gannon, 2005a). Currently, the focus of the
Wetlands Restoration Fund is shifting to include stormwater BMPs, including constructed wetlands. Since 1999, the
EEP has struggled to find good wetland sites for restoration (Rich Gannon, telephone interview Dec. 9, 2005). These
difficulties are reminiscent of the challenges encountered by wetland mitigation banking fee-in-lieu programs.
9.2.2 Program Performance
The Neuse NSW Strategy has been a success and has produced results similar to the Tar-Pamlico Program. The goal
of the trading program was to provide another option for achieving compliance with nitrogen allocations (Breetz et al.,
2004). As shown in Figure 9-6, the NRCA has been able to surpass the 30 percent TN reduction goal by more than
100 percent. NPS TN loads from agriculture have been reduced by 37 percent and 177 acres of riparian buffers have
been preserved (Gannon, 2005b).
One PS-PS trade that would raise the NRCA's nitrogen cap was considered in 2004, but was rejected because it was
found that the trade could potentially result in a hot spot (localized water quality problems) in Falls Lake, which is the
major drinking water supply for the City of Raleigh (Breetz et al., 2004; Gannon 12/2005).
9.2.3 Technical Performance
The Neuse Rules established a fixed fee-per-pound of TN discharged above the discharge limit allocated to the NRCA
and municipalities. In 1998, PSs were discharging 4.1 million pounds of nitrogen per year into the Neuse River Estuary.
In order to achieve a 30 percent reduction, PSs had to reduce their nitrogen contribution by 2.8 million Ib/yr. Nitrogen
allocated to individual dischargers was based on the ratio of their permitted ow to the total permitted ow of all PSs
(NCDENR, 1998).
NPS loading for the Neuse River Basin was originally estimated using export coefficients26 for different land cover types.
Land cover classifications were interpreted from LANDSAT imagery for 1993- 1995 (NCDENR, 1998). The modeling and
26 Export coefficient refers to the amount of substance, such as nitrogen, expected to be transported from land by stormwater
runoff. Expressed as amount of loading per acre per year (e.g., pounds/ac/yr).
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Ł
III
000
800
600
400
200
000
800
600
400
200
000
Estuary TN
Flow
(MGD)
Limit 1.073 M Ib/yr -f 80 -^
g)
70 i
60 S
50
120
110
100
90
Q
O
1995 1996 1997 1998 1999 2000 2001 2002 2003 2004
Figure 9-6 Neuse River NRCA performance, 1995 - 2004.
Point sources
24%
Agriculture
52%
Forest
14%
Figure 9-7 Sources of Nitrogen in the Neuse River Basin (1995).
information on PS loading determined that nutrient loads from agricultural operations account for more than 50 percent
of the nutrient load in the Neuse River Basin and PSs account for 24 percent; the remaining nutrient sources include
forest land, air, and urban areas (Figure 9-7).
The 30 percent nitrogen reduction goal was established before theTMDL process was concluded. Modeling to evaluate
the effects of various nutrient reduction scenarios was completed during the TMDL process to determine whether an
adjustment needed to be made to the 30 percent TN reduction target established by the Neuse Rules. Three models
were developed:
1. Neuse Estuary Eutrophication Model, a CE-Qual W2 application to the Neuse estuary;
2. Neuse Estuary Bayesian Ecological Response Network, a probability network model; and
3. Water Analysis Simulation Program, application to the Neuse Estuary. Two scenarios of this model were
run (NCDENR, 2001).
The results of these models confirmed that a 30 percent reduction in nitrogen from the 1995 baseline forTN is a rea-
sonable initial target (NCDENR, 2001).
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Based on the 30 percent reduction target, local governments were assigned a nitrogen export standard of 3.6 pounds/
acre/year. As previously discussed, new developments are required to implement on-site stormwater controls at least
to assure that nitrogen export from residential and commercial/industrial developments does not exceed 6 and 10
pounds/acre/year, respectively. Offset payments are required to meet the remainder of the requirement (Shabman and
Scodari, 2004; and Rules .0232, .0234, and .0240 of 15A NCAC 2B).
9.2.3.7 Nutrient Removal by Constructed Wetlands
Wetlands are recognized as playing a valuable role in the removal of nutrients from stormwater runoff in the Neuse
NSW program. As shown in Table 9-1, the standard TN and TP removal efficiencies of stormwater wetlands (also known
as constructed wetlands) developed by the NCDWQ for the purpose of monitoring progress toward nutrient reduction
goals is 40 and 35 percent, respectively. The Neuse NSW program has also generated several case studies on the
performance of constructed wetlands in various types of conditions.
In one such example, the NRET and Smithfield-Selma High School built a demonstration stormwater wetland to treat
runoff from parking lots, buildings, and the soccer field on the 70-acre school property in 1999. The created wetland
covers % acre in an area that was once a ditch. Students from the school participated in planting wetland plants and
continue to be involved in monitoring the performance of the wetland. The project cost $14,280 (NRET, 2004). Water
quality was tested using grab samples each August and December and following every storm event for a year and a
half. (An automatic monitoring system was not installed due to concerns regarding the potential for vandalism.) The
wetland has been very effective at removing nutrients and lowering water temperature: TN was lowered 85 percent, TP
was lowered by 93 percent, and average temperature decreased 3 degrees Fahrenheit. No seasonal variability was
observed in the level of nutrients removed from the wetland (Bill Lord, telephone interview December 9, 2005).
Assuming a linear relationship between construction costs and size of wetland, the unit cost of this wetland was $42,840
per acre.
Another example provided by the NRET illustrates nutrient removal efficiencies and also other factors that need to be
included in the selection of constructed wetlands versus other stormwater BMPs.This project was developed in conjunc-
tion with a plant nursery in Johnston County. A constructed wetland was built to reduce nutrients reaching the Neuse
River in 1998 and 1999. Because there was a growing demand for wetland plans, the constructed wetland was built to
double as a nursery for wetland plants. Preliminary water tests showed that the wetland was removing approximately
50 percent of the nitrate-nitrogen (NOs-N) (NRET, undated); however, the wetland attracted snakes and the project was
discontinued (Bill Lord, telephone interview December 9, 2005).
Demonstration projects have also revealed that constructed wetlands can have mixed results. Prior to the adoption of
the 1997 Neuse NSW Strategy, a pilot project was completed in the South River, located near the mouth of the Neuse
River. Residential, forestry, and agricultural land uses are dominant in the watershed. A constructed wetland was de-
veloped on a 10-acre parcel of converted cropland adjacent to Southwest Creek. Blocked in ow ditches were opened
and an out ow structure put in place to reestablish the wetland hydroperiod and raise water tables of approximately
300 acres of upgradient cropland.27 The restored wetland removed more than 90 percent of the NH4-N and 97 percent
of the NOs-N from the field out ow; however, phosphate phosphorus increased by 30 percent, possibly due to a reduc-
tion in pH (NCDENR, 1998).
Similar results were observed in another wetland project in the Chowan River Basin in the northeastern part of North
Carolina (Figure 9-1), in the Town of Edenton. A two-year study was conducted by Kristopher Bass (2000) as a part of a
Masters thesis to quantify impacts of an in-stream constructed wetland on water quality. The 2.4-acre in-stream wetland
was built to intercept drainage waters from approximately 600 acres of agricultural and urban watershed, which resulted
in a wetland-to-watershed area ratio of 0.004:1. During the project, NOs-N concentrations were reduced through the
wetland by 60 percent; NH4-N concentrations by 30 percent, and TKN levels by 9.5 percent.This resulted in a 20 percent
drop in TN concentration. TP levels increased 55 percent between the wetland inlets and outlet. Seasonality of wetland
performance was also evaluated. Bass (2000) found that NH4-N concentrations decrease by 10 percent more during
the growing season; TKN concentrations decreased 15 percent during the winter and not at all during the summer; and
TP was higher during the summer than in winter. In summary, he found that nutrient reductions were generally associ-
ated with temperature changes, and higher temperatures resulted in greater NH4-N and NOs-N reductions and larger
increases in TKN and TP (Bass, 2000).
The results reported by Bass (2000) indicate a relationship between nutrient removal efficiencies and temperature/sea-
sonality. However, seasonality in nutrient removal efficiencies was not observed at the Smithfield-Selma High School.
An evaluation in the relationship between the effects of seasonality/temperature and the wetland-to-watershed areas
ratio may provide insight into design of more effective constructed wetlands.
27 If 300 acres is the total area serviced by the wetland, the ratio of area to wetland is 1:0.033.
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9.2.4 Economic Performance
The unit offset payment adopted by the Neuse Rules was originally set at $11 per pound (15A NCAC 2B.0240). Offset
payments are required to include money for 30-year O&M, which is undertaken by a government entity such as a lo-
cal government or community college (Gannon, 2005a). In addition, new or expanding PSs or offsets purchased by
the NRCA are multiplied by 200 percent to account for uncertainty (15A NCAC 2B.0240). However, under the urban
stormwater rules, developers are not required to multiply offset payments by 200 percent. As a result, a discharger
needing to purchase an offset for 1 pound of nitrogen would pay an effective fee of $660 per pound, and a developer
would pay $363 per pound.
The $11-per-pound offset was based on the cost of restoring degraded wetlands. However, revisions to the offset
rate, which would raise it to $57 per pound, are currently being made to 15A NCAC 2B.0240. The change in the offset
fee is due to a shift in the focus of the EEP to stormwater BMPs. Over the past years, the EEP has struggled to find
appropriate sites for wetland restoration. The $57-per-pound offset rate re ects the higher price of this sort of BMP
(Table 9-2). In addition to the revision to the offset rate, the applicability of the regulation will be expanded to apply to
the entire state (including Tar-Pamlico), and the Neuse River Basin nutrient reduction goal (15A NCAC 2B.0232) will
be expanded to include a reduction target forTP (Rich Gannon, telephone interview, December 9, 2005). The draft
revisions to the regulations also proposed revisions in calculating the total offset fee. The revised offset fee calculation
is presented below:
EEP Offset Rate:
N offset (Fee) = [$57/lb (lb/yr)(30 years) + $/ac(1/35)(ac developed)] x 1.1
Where $57 is stormwater BMP cost (?)-effectiveness, (Ib/yr) is reduction needed, 30 years is the BMP life
span, $/acre is cost of developed land, 1/35 is the BMP/drainage ratio, and 1.1 is an administrative cost
factor.
Phosphorus (Fee) = $45/0.1 Ib x same as above
Note: for wastewater load offsets, the land cost factor = 0 (Gannon, 2005a)
There is no trading ratio for PS-PS trades, nor is the NPS offset fee paid to the Wetlands Restoration Fund (Breetz et
al., 2004).
9.2.4.7 Constructed Wetland Construction Costs
Wetland construction costs fall into three main categories: land, construction, and maintenance. Land cost is, of course,
the most variable, depending on location, but is often the largest single cost associated with wetlands in North Carolina,
especially in urbanizing areas. (Hunt and Doll, 2000). Research completed by Hunt and Doll (2000) and Wossink and
Hunt (2003a) developed the following cost estimates for various components of wetland construction based on a series
of case studies:
• Excavation and grading: this category of costs for wetlands constructed in the Piedmont and Coastal Plain of
North Carolina have ranged from $4 to $9 per cubic yard, with a tendency toward economies of scale. Hauling costs
dramatically increase with the distance the excavated soil needs to be carried (Hunt and Doll, 2000).
• Land: (1) undeveloped land for commercial use with an average opportunity cost of $5 per square feet ($217,800 per
acre); (2) undeveloped land for residential use with an average opportunity cost of $50,000 per acre; and (3) unde-
veloped land with zero opportunity cost because of the requirement for open space (Wossink and Hunt, 2003a).
• Vegetation: the species of wetland vegetation can greatly affect costs. Costs have ranged from as low as $0.30
per square foot where plants came from selective harvesting and natural establishment to $1 per square foot where
nursery vegetation was used (Hunt and Doll, 2000).
• Outlet and drawdown structures: costs of the principal outlet and drawdown device depend on the size of the
wetland and have ranged from $0.25 to $1 per square foot of wetland area (Hunt and Doll, 2000).
Costs for constructing wetlands and other stormwater BMPs in North Carolina are compared in Table 9-3.
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Table 9-3 Summary of Construction Cost Curves, Annual Maintenance Cost Curves, and Surface Area for Five
Stormwater BMPs in North Carolina
Range of BMP size (acres)
Cost
Construction
20-year maintenance
Surface area
Residential development:
• Piedmont
• Coastal Plain
Highly impervious area
(CN80)
• Piedmont and Coastal
Plain
100% impervious
Wet ponds
0.75-67
C= 13,909 x
0.672
C = 9,202 x
0.269
SA= 0.015 x
SA = 0.0075 x
SA = 0.02 x
SA = 0.05 x
Constructed
wetlands
4-200
C = 3,852 x
0.484
C = 4,502 x
0.153
SA = 0.020 x
SA = 0.01 x
SA = 0.03x
SA = 0.065 x
Sand filters
0.5-9
C = 47,888 x
0.882
C = 1 0,556 x
0.534
SA = 0.017 x
Bioretention in
clay soils
0.3-9.2
C = 10,162x
1088
C = 3,437x0.752
SA = 0.025 x
SA = 0.015 x
SA=0.03x
SA = 0.070 x
Bioretention in
sandy soils
0.3-9.2
C = 2,861 x 0.438
C = 3,437x0.752
SA = 0.025 x
SA = 0.015 x
SA = 0.03 x
SA = 0.070 x
Source: Wossink and Hunt (2003a). Note: C = cost in $. x = size of watershed in acres. SA = surface area in acres.
This table illustrates that stormwater wetlands are less expensive to construct and maintain than wet ponds, but wet
ponds require a much smaller surface area to effectively treat stormwater runoff. Bioretention is the least expensive
option for treating stormwater from smaller sized watersheds. The cost curves do not include land costs; as the cost of
land increases, wet ponds would become more cost-effective than stormwater wetlands.
Table 9-4 provides a cost comparison for four stormwater BMPs for a 10-acre watershed and the nutrient removal ef-
ficiencies of each BMP.
Table 9-4 Cost Comparison of Four BMPs for 10-Acre Watershed (CN 80a)
Practice
Construction cost
Annual maintenance cost
Opportunity cost of land ($217,800/acre)
Present value of total cost
Annualized cost per acre watershed
Wet pond
$ 65,357
$ 4,411
$ 43,560
$ 146,474
$ 1,721
Wetland
$ 11,740
$ 752
$ 65,340
$ 83,486
$ 981
Bioretention in
clay soils
$ 124,445
$ 583
$ 65,340
$ 194,751
$ 2,288
Bioretention in
sandy soils
$ 7,843
$ 583
$ 65,340
$ 78,137
$ 918
Annualized cost per 1 percent of pollutant removal
TSS
TN
$26
$61
$15
$45
N/A
$51
N/A
$20
Source: Wossink and Hunt (2003b). N/A = not applicable.
a Curve Number (CN) reflects the ability of a watershed to store water through initial storage and subsequent infiltration. A high CN indicated a
watershed with limited storage capacity.
9.2.4.2 Program Costs
There is incomplete information available on the total costs of the Neuse NSW Strategy. Aside from the initial funding of
$500,000 annually for the NRET, which has been reduced in recent years, information on other costs associated with
the program is not readily available. The state, rather than the NRCA, assumes most of the transaction costs associated
with NPS offsets (Breetz et a/., 2004).The $11-per-pound offset payment can be compared to the $25- to $30-per-pound
nitrogen control costs estimated for PSs elsewhere in North Carolina (Environomics, 1999); however, the requirement
that credits be purchased for a 30-year period pushes the total cost higher than state-wide average costs.
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9.2.5 Administrative Performance
The NCDWQ, NCEMC, and EEP administer the Neuse NSW Strategy. As with the Tar-Pamlico, it is the responsibility
of PSs and NPSs to demonstrate compliance with the Neuse Rules. The NPDES permits of PSs within the NRCA do
not contain a discharge limit for TN; the TN limit for the NRCA is specified in the group compliance NPDES Permit
(USEPA, 2002b).
Each co-permittee has been assigned a TN allocation, but that is subject to change due to purchases, sales, trades,
leases, and other transaction among the NRCA members. Furthermore, if the membership of the NRCA changes, the
group TN allocation is changed in the group compliance NPDES permit accordingly. Members of the NRCA monitor
discharges and report results to the NCDWQ, as specified in their NPDES permits, and to the NRCA. The NRCA com-
piles the co-permittee reports for its own reporting. As a group, the NRCA submits mid-year, year-end, and five-year
reports (USEPA, 2002b).
Offset payments are paid to the EEP and tracked by an "In-Lieu Fee Coordinator," a staff position created to administer
the program. North Carolina State University and local governments assist the EEP in identifying potential projects.
The offset BMP projects are located no farther from the estuary than the loading being offset (Gannon, 2005a). Offset
BMP projects are awarded to an on-call EEP contractor pool. The contractors are responsible for design, construction,
and one year of performance monitoring (Gannon, 2005a). There are currently numerous projects in design (Gannon,
2005a).
9.3 Summary
The Tar-Pamlico and Neuse River Basin NSW implementation strategies were both successful at reducing nutrient
loads. By 2003, nitrogen had been reduced in the Tar-Pamlico and Neuse River basins by 34 percent over 10 years
and 37 percent over 7 years, respectively (Gannon, 2003). Furthermore, the associations of PSs created by both pro-
grams have successfully attained nutrient reduction targets. Although no PS-NPS trades have occurred, the structure
is in place so that this option is available if needed in the future. As a result of these efforts, water quality has been
improving in the Pamlico Estuary.
The Neuse NSW Strategy may have been successful at reducing nutrient loads faster than the Tar-Pamlico due to two
key factors.
1. By the end of 2002, the target year for full implementation of the Neuse Rules was nearing (the rules were
adopted in 1997). NPSs had been legally required to meet nutrient reduction goals for over four years,
whereas the Tar-Pamlico Rules did not take effect until 2000-2001.
2. From the outset, the Neuse was allocated significant new resources in the form of field staff to facilitate
BMP implementation and NPS education programs. It also received significant new cost-share funding for
the entire period. No new resources were allocated to the Tar-Pamlico program between 1997 and 2002
(Gannon, 2003). Education of the agricultural community on their role in NPS nutrients was important in
both programs.
The NSW strategies for both basins were developed concurrently and relied heavily on public and stakeholder input. The
key goals of both strategies were to reduce eutrophication and to provide sources of nutrients with exible options for
achieving nutrient reduction goals. Each program developed innovations that the other adapted: Tar-Pamlico developed
the WQT program for PSs first and Neuse developed regulations to address NPSs of nutrients first.
There are several key differences between the two programs:
• The Tar-Pamlico has not adopted rules to allow NPS-NPS trading.
• Tar-Pamlico targeted agricultural BMPs for offset projects to reduce NPS nutrient loads. Neuse River Basin targeted
wetland restoration and (recently) stormwater BMPs. Adoption of the Tar-Pamlico Agriculture Rule likely raised the
stakes with respect to the potential offset BMPs projects - the rules do not allow double counting of nutrient reduc-
tion, so agricultural offset projects would need to be in addition to what agricultural producers were already required
to do. Given that the least expensive BMPs are likely to be implemented first, this is likely one of the reasons the
offset rate paid to the EEP is being increased.
• The methods used to calculate offset fees and the estimated life span of BMPs is very different between the two
programs. A 10-year life span is assigned in the Tar-Pamlico program compared to a 30-year life span in the Neuse.
There appears to be a need for further research into the life span of the nutrient removal BMPs and how they change
over time. Work is currently being done in the Tar-Pamlico program to address uncertainty regarding the life span of
credits and how to deal with temporal issues related to when credits are generated versus when they are used.
The one failed PS-PS trade between an NRCA member and a non-NRCA member in the Neuse River Basin dem-
onstrates the strength of regulatory checks and balances, but a potential weakness in both programs. The trade was
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not approved due to the potential for localized water quality impacts. However, trading among NRCA members does
not require NCDWQ approval. This may be resulting in localized water quality impacts that neither program seems to
address.
Other lessons learned from the Tar-Pamlico Program relate to development of the initial baseline estimates of nutrient
loads from various sources and program funding. Farmers perceived that the baseline for Phase II reductions did not
adequately account for BMPs that had already been implemented voluntarily. Some believed better documentation of
voluntary progress might have precluded the need for regulations (Breetzef a/., 2004). Administering trades through the
Cost-Share Program streamlined the program in many ways, but Cost-Share staff ran into difficulty predicting available
funds and staffing needs in Phase II, when the NRCA was no longer required to make minimum payments for these
purposes (Breetz et a/., 2004).
9.3.1 Unanswered Questions
• Seasonality and the nutrient removal efficiency of wetlands: The Bass study (2000) provided some information on
the effects of season; however, given that the constructed wetland monitored during this study was undersized, it
is unclear whether the same results would have been observed in a wetland that was appropriately sized.
• Nutrient removal efficiency of wetlands over time: wetland monitoring data available for this case study spanned
short time periods (approximately two years), but the information is inconclusive regarding how wetland nutrient
removal changes over time.
• What is the life span of the nutrient removal BMPs?
• What is the effect of BMP maintenance on nutrient removal efficiencies?
• Does nutrient removal efficiency of a BMP change as the concentration of nutrients in the in owing water increases
or decreases? Are some BMPs better than others for removing nutrients at higher or lower concentrations?
• How were the land-based accounting methods developed? How accurate are they?28
28 This has a much broader application than just WQT.
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10.0 Synthesis/Summary of Findings
The information provided by the literature review and case studies is summarized here into key observations illustrated
by comparisons among the case studies. These observations integrate the scientific, economic, and regulatory elements
of trading to identify opportunities, potential hurdles, and unknowns for a very select set of trading pilot projects and
programs attempted to date in the United States.
10.1 Performance Monitoring versus Conservatism
Most of the evaluated trading programs bypass performance monitoring for quantifying NPS load reductions and instead
use conservative estimates (i.e., underestimates) of effectiveness to determine the amount of wetland required to achieve
the desired nutrient load reduction. Safety factors are used to increase confidence in performance. The Cherry Creek
trading program, a notable exception, requires direct measurement of nutrient load reduction, but creating an in ow point
and an out ow point for the constructed wetland accommodates this. For the other program examples, implementation
of BMPs was documented, but actual performance in reducing nutrient loads was presumed based on estimates and
safety factors not substantiated with monitoring data. The rationale for using this approach stated that monitoring was
either not feasible or prohibitively costly to the degree that it was more cost-effective to grossly oversize the wetlands
to overcome uncertainty about performance.
While there is a wealth of scientific information on the function of various types of wetlands in removing nutrients, the
literature does not report that anyone has yet compiled the available information into a comprehensive tool that can be
used to assess the many interrelated factors affecting wetland performance that makes each wetland unique. Such a
tool would provide confidence in designing or determining the performance of constructed wetlands in reducing nutrient
loads. In Idaho, for example, the ISCC recommended against using constructed wetlands for calculated credit because
currently there are not enough data to determine efficiency or uncertainties at a scale larger than a single site (ISCC,
2002). A primary challenge is to quantify baseline conditions, i.e., the site load prior to BMP application. The degree to
which headwater wetlands may treat pollutants and contribute to the baseline should be considered. Many interrelated
parameters, including seasonality, changes in retention rates with varying loads and overtime, drainage patterns, rela-
tive location of a wetland within the watershed, and type of wetland, drive wetland performance according to system
dynamics.
The incorporation of safety factors, which increase the amount of wetland required to produce the necessary perfor-
mance, may mitigate the limitations due to these uncertainties. Therefore, in the absence of monitoring data, performance
is presumed based on gross conservatism. Unfortunately, not only is this approach potentially cost-prohibitive, it also
fails to manage uncertainty regarding non-target pollutants. Specifically, the management of one stressor affects the
fate and transport of other contaminants, potentially releasing them from wetlands. For example, a wetland's role as a
greenhouse gas and methyl mercury sink or source affects its benefit to the ecosystem.
There may be an opportunity to reduce uncertainty and increase program potential by establishing objective and reliable
means of determining performance of constructed wetlands. One approach would be to develop more cost-effective and
adaptable guidelines for collecting monitoring data. Another solution would use a combination of existing information
and new research to develop general performance data to inform the creation of generalized calculation guidelines for
estimating performance. For this strategy to succeed, it must acknowledge the wetland's dynamics and resulting changes
in retention rates within the context of the larger geographic scale. Establishing baseline nutrient levels and mapping
the wetlands in the watershed will serve to more accurately quantify these rates. Finally, historical contamination in the
wetland may also justify monitoring of non-target pollutants.
10.2 Motivations for Nonpoint Source Participation
NPS contributors are difficult to regulate due to the challenges in isolating and quantifying the contributions of individual
parties. Nevertheless, for many watersheds, NPS nutrient load contributions exceed PS contributions, as illustrated by
the case studies documented in this report. WQT programs may be used to create an economic incentive for NPSs to
control their contributions through trading the load reductions fora profit. This is feasible in certain circumstances based
on the significant difference in costs.
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NPS contributors have a subtle disincentive to participate in trading programs. While they may benefit financially by
reducing nutrient loads, the financial gains may be offset by potential liabilities associated with new compliance require-
ments, or strict enforcement of existing compliance requirements they currently do not meet. "Additionality" stipulates
that any offset that would have occurred regardless of the trading program cannot count toward a trade—e.g., BMPs
that are already required of farmers cannot be used to create trade value. Presumably, if reliable methods are developed
to isolate and quantify NPS load reductions, those same methods may be used to facilitate more effective regulation
of NPSs. Ultimately, a thorough understanding of nutrient loading on a watershed scale is necessary to align the right
incentives for NPS contributors to participate. WQT programs may provide a viable mechanism to increase the partici-
pation of NPSs in implementing BMPs to improve water quality. Trading programs may provide a platform for education
and means by which landowners receive outside funds to make improvements to their properties by implementing BMPs
and to generate more valuable data for better scientific assessment of water quality conditions.
Ancillary benefits to property owners may be enough to motivate participation in NPS load reduction actions. In the Rahr
nutrient trade, bank stabilization and riparian habitat restoration were used to reduce nutrient and sediment loads. The
property owners received the benefit of a stabilized riverbank that protected their property from future loss.
Cooperation among stakeholders is essential to success. Rahr established collaborative relationships with environmen-
tal organizations, MPCA, and the NPSs so that everyone perceived that all parties were working together for the best
interest of the environment.
10.3 Effects of Compliance Thresholds and Enforcement
The "maturity" of the trading market is a strong determinant for the feasibility of trades. The Cherry Creek trading program
illustrates this point clearly. The load allocations were assigned to PSs allowing for projected growth capacity. Since the
PSs are, at current capacity, easily able to operate within their compliance limits, there is no demand for trades. As PSs
grow and increase their capacity, it will become more difficult for them to operate within the same load allocation limits.
At some future point, nutrient trades will become economically preferable in comparison to facility upgrades. In contrast,
Rahr was unable to obtain a permit to discharge into the Minnesota River unless its contribution was entirely offset by
trades. Based on the success of the Rahr trade, a general permit was established following the same form to guide
future applicants. Enforcement of discharge limits will also affect participation in trading. If the discharge limits are strict
enough they necessitate trading, but if the likelihood of enforcement when limits are not met is remote, dischargers may
decide to game the system instead of participating in trading. Therefore, stringent permit limits with strict enforcement
significantly motivates PS demand for trading. The four case studies suggest that NPS participation eventually follows,
matching supply to the demand.
70.4 Comparison of Program Structure
Trading programs vary among the case studies in terms of how the structure guides and regulates trades. The Rahr
example in Minnesota illustrates how a single set of trades can be incorporated into the terms of an NPDES permit for
a single PS. The Tar-Pamlico program in North Carolina established an association of PS and NPS contributors who
were collectively regulated and allowed to trade among themselves to achieve group compliance. No trades have oc-
curred in either of the North Carolina case studies. The exibility afforded by the group compliance option has allowed
members within the Tar-Pamlico and Neuse compliance associations to informally trade amongst themselves (Breetz et
a/., 2004). As opportunities for cost-effective technology upgrades are exhausted, trading will likely occur in the future.
The Cherry Creek program in Colorado establishes two entities that accomplish NPS reductions and build up a credit
bank for sale. The LBR program in Idaho allows for trades to occur freely between trading partners required to report
the trade to the regulatory authority for review, monitoring, and approval.
70.5 Credit Life
Considerable work has been completed evaluating time limits orthe useful life of BMPs. In general, a life span of 10 years
for structural and 3 years fornonstructural BMPs has been the norm in trading programs; however, the Idaho and Neuse
River programs extend credit life beyond that to 15 and 30 years, respectively. There are still questions regarding what
happens after credits expire; how to deal with temporal differences between when the credits were generated and when
they are applied; what happens if credits are generated and not used; and how to better understand and predict the
short- and long-term assimilative capacities for a given wetland considering seasonal variation in performance.
70.6 Economic Challenges to Trading
As discussed in Section 4.0, efficiency requires that at least one source be able to more cost-effectively reduce its
discharges than another source; otherwise, the program would not be financially attractive nor marketable (Fang and
Easter, 2003; Jaksch, 2000).
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It is essential that economic considerations support WQT for it to be a viable tool to achieve water quality standards.
Economic trading challenges suppress WQT by making net economic value of trading less attractive than alternate
compliance management strategies due to risks and uncertainties. Four economic challenges threaten the development
of robust, sustainable WQT programs because they reduce the DCFROI, the future return on investment in relation to
capital costs associated with generating credits, of trading. These are: (1) simplified modeling of natural system impacts
which leads to overly conservative trading ratios, (2) costly environmental protection, (3) high transaction costs, and
(4) ill-defined property rights. These challenges hinder efficient and fair deal making, usually because they make the
risk and/or return on investments in WQT high to the buyer, the seller, or both.
There are a number of potential solutions to address the economic gaps and challenges that complicate the value and
risks associated with trading, such as:
• Improving the efficiency of regulatory activities: this could include special training for agency staff, dedicated
WQT agency staff, clarification of legal issues that reduce disputes, improved system modeling, and simplified
data management. Implementing these measures is both technically and economically feasible. However, it would
require upfront investment by regulatory agencies in improving staff, policies, practices and equipment. Some of
these costs could be recaptured by administrative costs built into offset fees. Limiting regulatory involvement to
setting the minimum rules of engagement would maximize regulatory efficiency.
• Increase the command and control compliance liability for PS: stricter PS discharge limits should increase
the economic attractiveness of WQT, encouraging more trades and better environmental protection. However, very
careful consideration and justification would be required before selecting this option. PSs and other stakeholders
could potentially argue these changes are unfair in light of the NPS contribution to watershed nutrients in many
watersheds.
• Market and non-market economic valuation of natural systems: establishing market and non-market economic
valuation of a natural system, such as a watershed, would take into account the economic value of the system or
system components (e.g., ood control, drinking water, fisheries) and the parties that derive value from those com-
ponents (municipal government, commercial fishermen, tourism industry, etc.). The outcome of this analysis would
furnish a more comprehensive understanding of the economic values of these systems and the key stakeholders,
yielding more informed decisions. For example, the analysis could provide potential traders with an understanding
of how else they benefit directly from implementing a BMP. In addition, this analysis could identify other potential
markets for the ecological services delivered by wetlands. Suppliers would realize a greater return for their invest-
ment, thereby encouraging their participation. Methods for determining economic values are well established and
can be useful in informing long-term policy, and they could provide potential traders with additional information on
the benefits that they may derive from participation in trading. Other than the generated credits for sale, other returns
may also add value for the seller, thereby promoting WQT. Ironically, the non-market value of ecosystem components
is considered less important unless and until natural events occur that make value more "real" to residents within a
watershed. For example, fish kills in the Neuse and Tar-Pamlico provided the impetus for bringing about changes
in how those watersheds are managed. Likewise, coding in the wake of hurricanes Katrina and Rita raised the
profile of the utility of levees and dikes and coastal wetlands that protect the shores of Louisiana.
• Economic Analysis Tools: Many economic analysis tools already exist and they could be applied specifically to
WQT. These tools include: economic investment decision methods, which could employ techniques for calculating
DCFROI to demonstrate long-term value of WQT and support decisions of potential WQT participants; and proba-
bilistic analysis, which would allow a thorough evaluation of risk. For example, World Resource Institute's "Nutrient
Net" allows PS and NPSs to evaluate cost-benefits of trading specific to their watershed application. Such analyses
could be used to compare the value of wetlands versus other BMPs. If regulators develop platforms for performing
this type of analysis, then individuals can use them to perform their own analyses of the risks and opportunities
associated with participation.
With respect to risk, credit prices in WQT programs have not tended to be structured to compensate sellers for their
risk in implementing BMPs and engaging in WQT, presumably because the opportunity to create private value is sub-
stantial relative to the risk to engage in activities for the purpose of improving water quality. For example, in Idaho,
while the NPSs were not driven by regulation, they recognized the opportunity to improve their property free of charge
without acknowledging measurability of their loads. In ideal markets, investors build their cost of risk into the price of
their goods and services. Not pricing credits to include the cost of investor risk might be an important reason that WQT
supply and trading are suppressed if the NPS feel they are not getting enough of a return for their risk. Likewise, not
pricing credits to include the opportunities associated with investor risk might also suppress WQT supply. At a minimum,
efforts to increase the awareness of the value generated beyond credit prices, e.g., market and non-market economic
valuations, may increase the attractiveness of participating in trading to potential credit sellers. Complicating matters,
credit prices are also affected by investor risk, and opportunities on the supply curve will in uence the intersection with
the demand curve.
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Prices of credits will re ect risk if the market is allowed to function without too many restrictions.
70.7 Property Rights and Transfer of Liability
WQT programs have taken different approaches to issues associated with property rights and transfer of liability. In all
cases, NPDES liability remains with the PS discharger. However, the question of who would be contractually liable if
a BMP project fails is addressed slightly differently in each of the WQT programs included in the case studies. In the
Cherry Creek, Rahr, and Idaho programs, the credit purchaser is not offered a release from liability if the mitigation is
ineffective and may be faced by the need to continuously monitor and maintain the mitigation measures implemented
to generate credits. In the Tar-Pamlico and Neuse programs, a third party takes on the liability for BMP maintenance.
The transfer of liability from the credit purchaser to the third-party mitigator was identified as critical to making wetland
mitigation banking work: credit purchasers are interested in rapid permitting and avoidance of liability if a mitigation site
fails; creating healthy wetlands is secondary to the decision to purchase nutrient credits from the mitigation bank. The
lingering liability attached to trades in the first three programs exposes the buyer to risk. Making a nutrient trade does
not eliminate the possibility that the same discharge issue could arise again some time in the future. As a result, the
unknown risk associated with trading plus additional costs and logistics associated with monitoring BMPs implemented
on the credit seller's property make WQT less attractive to PSs.
As previously discussed, many trading programs put time limits on the useful life of credits. If a wetland has been restored
or enhanced to generate credits for a WQT trading program, there may be regulatory implications associated with what
happens to the wetland after the credits expire. The wetland could become regulated under the CWA, thereby limiting
potential uses of the land. This could serve as a deterrent to using constructed wetlands as a BMP in WQT programs.
There may also be implications to drinking water supply issues. If the USERA and states would like to encourage the use
of constructed wetlands in WQT programs, then the long-term regulatory implications of building constructed wetlands
to generate credits for WQT programs will need to be clarified.
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11.0 Research Recommendations
The literature review and case studies in this report illustrate the need for additional research for WQT programs to
successfully integrate NPS nutrient load reduction through the use of constructed wetlands. Specific research topics
are grouped into three categories that mirror the structure of the study: (1) technical research needs, (2) economic re-
search needs, and (3) regulatory and administrative research needs. Many of the specific recommendations integrate
components across the range of these categories.
11.1 Technical Research Needs
While several examples illustrate the feasibility of WQT programs involving wetland creation for NPS trades, there are
several elements of such programs where uncertainty is mitigated by applying conservative factors of safety. The case
studies illustrate that in practice, program participants presume it is more cost-effective to create larger wetlands than
to directly measure the effectiveness of the constructed wetland. These areas of uncertainty present opportunities for
improving trading program efficiency and economic viability.
There are two distinct areas of uncertainty associated with the performance of wetlands in reducing NPS nutrient loads.
The first involves the ability to quantify the performance of a discrete wetland in reducing nutrient load. Many factors
in uence nutrient removal efficiency, and these factors relate to one another in complex ways. The dynamic nature of
the system compounds these complexities. The second area of uncertainty involves the ability to translate nutrient load
reductions spatially throughout a watershed.
11.1.1 Individual Wetland Performance
Some trading programs concluded that performance monitoring was either not feasible or prohibitively costly to the
degree that it was more cost-effective to grossly oversize the wetlands to overcome uncertainty about performance.
Literature does not re ect a compilation of the abundance of scientific information pertaining to the function of various
types of wetlands in removing nutrients into a comprehensive tool that can be used to consistently and confidently design
or determine the performance of constructed wetlands in reducing nutrient loads. This limitation does not prevent NPS
nutrient trades involving wetlands. Instead of precisely determining the load reduction associated with wetland creation,
the uncertainty associated with estimating techniques is mitigated by incorporating safety factors. This approach greatly
multiplies the amount of wetland required to ensure the necessary performance. Several possible research topics emerge
to address uncertainty in wetland performance:
• Define the minimum performance monitoring data requirements to determine water quality credits and determine
the optimum distance downstream of the wetland for monitoring. Accordingly, collect data to satisfy these data
requirements for a few pilot projects to validate presumed load reductions.
• Collect performance data documenting the effect of various maintenance activities on prolonging optimal performance
in removing nutrients. Determine the deterioration of performance with time in the absence of maintenance.
• Gather additional data on the cyclical and long-term trajectory of nutrient removal by various types of constructed
and restored wetlands.
• Compile scientific information pertaining to the function and effectiveness of various types of wetlands in removing
nutrients and the long-term trajectory of nutrient removal overtime. Use these data to create a comprehensive tool
that can be used to assess the many interrelated factors affecting wetland performance. Such a tool would provide
confidence in designing or determining the performance of constructed wetlands in reducing nutrient loads. This
information would also facilitate nutrient removal modeling and aid calculation of nutrient credits.
• Perform additional literature review and analysis focused on the effects of seasonality on the nutrient removal ef-
ficiency of wetlands. Consider the reliability of annual nutrient removal to suitably re ect wetland performance.
• Perform additional literature review and analysis to comprehensively assess the variability of nutrient removal by
ecoregion.
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• Research effects of atmospheric deposition of nutrients, particularly NOx, and how to incorporate them into wetland
design.
• Determine the effect of in ow nutrient concentration on removal efficiency of various BMPs. Does nutrient removal
efficiency of a BMP change as the concentration of nutrients in the in owing water increases or decreases? How
do upland land uses affect pollutant inputs? Are some BMPs better than others for removing nutrients at higher or
lower concentrations?
• Develop better models, methods, and tools to cost-effectively predict and monitor performance of nutrient removal
BMPs to eliminate having to measure performance to generate credits and to allow for design exibility.
• Gain insight into how to optimally locate a wetland within the landscape and into how an existing wetland's location
affects its utility as a nutrient reducer with which to trade credits and thus the value of those credits. Administrators
could then assemble a list of potential sites from which PSs seeking an NPS trading partner could choose. Ad-
ditionally, the design and performance would benefit from this insight.
• Conduct research on the long-term fate of nutrients removed using constructed wetlands.
• Refine the current body of knowledge on transmission losses and uptake capacity of nutrients between the trading
partners. Develop standard methods for discounting credits as the distance between the buyer and seller increases
and as the distance of the BMP from the water body increases. This would help administrative bodies to ensure
that localized water quality impacts do not occur as a result of a trade and determine whether "total mass" caps for
PSs need to be set to prevent localized impacts.
• Refine methods to accurately account for differences in constituent speciation or even the type of constituent. The
inability to do so results in overwhelmingly conservative safety factors, which can sti e trading or at least limit trad-
ing participants.
• Review how land-based accounting methods were developed and assess their relative accuracy compared to direct
measurement. Determine the key areas of uncertainty and design research programs to address them.
• Establish quality assurance/quality control of monitoring.
11.1.2 Watershed-Scale System Dynamics
Describing the integration of multiple PSs and NPSs and transport processes requires sophisticated tools. Character-
ization of spatial and temporal effects on nutrient loads is necessary to evaluate and document the effectiveness of
transferring load reductions in time and space. Such comprehensive evaluations on system performance should consider
the effects on other stressors and their impacts, e.g., the fate and transport of residual contaminants in the wetlands.
Likewise, performance should assess the sensitivity of operational and engineering parameters on nutrient removal
and, more generally, on ecosystem integrity. This knowledge is necessary to ensure that WQT contributes to meeting
watershed-scale water quality management objectives without unduly compromising local water quality or introducing
undesirable temporal effects.
SDA can facilitate the success of WQT by reducing uncertainty and quantifying risk. The capabilities of this tool to evalu-
ate the complex events and phenomena inherent in many systems are critical to achieving a thriving WQT market that
is protective of the environment. SDA provides the platform to account for risk by (1) thoroughly modeling and analyzing
complexity, (2) minimizing assumptions and simplistic functions, (3) allowing exibility in time and space, (4) allowing
a stress test of baseline conditions, (5) facilitating sensitivity analyses, (6) modeling complicated feedback relations,
and (7) allowing model upgrades to best available science, as better knowledge and information become available.
This approach establishes expected values for each model input and the expected value of a given strategy. With SDA,
conservative contingency factors and trading ratios are minimized or obsolete. For example, trading ratios are replaced
with analyzed values that represent break-even values; i.e., ratios which realistically balance nutrient loads into a water-
shed, for regulators. SDA is a very effective tool for evaluating how complex systems will behave as a result of change.
This tool can provide insight into how factors interrelate. Ultimately, data for specific watersheds could be inputted, with
literature values substituting for unknown data, into a general SDA model.
77.2 Economic Research Needs
The following economic research recommendations focus on determining value and risk associated with strategies that
use wetlands to reduce nutrient loads.
• Perform complete economic valuations of strategic alternatives that involve WQT and develop tools that potential
trading participants could use to quantify the value of investing in WQT as a nutrient management strategy of choice.
Include environmental uncertainties in economic models for such valuations.
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• Determine the interaction of factors hindering participation in a WQT market; e.g., cost-prohibitive discount ratios,
unlikelihood of enforcement, lack of incentives, or fear of future liability. Use comprehensive understanding of the
system and clearer guidelines to overcome these challenges.
• Quantify supply-demand curves and factors affecting them. Use this information to determine whether a WQT market
is a viable solution in a de-regulated environment.
• Search for evidence of free market applications of WQT. If available, compare benefits and challenges with regulated
case studies reviewed for this report.
• Identify additional economic incentives for BMPs when credits are not available (e.g., budgeting payments during
seasonal needs for nutrient reduction) that would foster NPS participation.
• Assess viability of designing wetlands in advance and banking credits to meet daily and monthly needs.
• Investigate the feasibility of making trading credits available for multiple environmental amenities (e.g., water quality,
endangered species, ood control) provided by BMPs such as restored or constructed wetlands. This would need to
be supported by thorough public market valuations for the functioning BMPs overtime. Integrating multiple concurrent
ecological values enhances the opportunity to improve the returns credit sellers are able to make by building BMPs
on their property and the opportunity costs associated with not using that land for other purposes. The implementa-
tion of the 2007 Farm Bill will test the feasibility of using Federal funds towards BMPs for credit generation.
• Evaluate cost effectiveness of the wetlands design. Compare the effectiveness of more, but smaller, wetlands versus
fewer, but larger, wetlands. Include among the various costs, those associated with monitoring and maintaining the
wetlands.
• Research how considerations of scale affect economic decisions and how related uncertainties can be ad-
dressed.
• Probe the sociological drivers affecting entry into the market and evaluate the feasibility of incorporating these into
economic models.
• Identify lower-cost engineering solutions for constructed and restored wetland design and maintenance.
11.3 Regulatory and Administrative Research Needs
Regulations and policies steer the administration and performance of WQT programs, sometimes in unforeseen or un-
desirable ways. The following research recommendations anticipate some such effects and target administrative steps
or tools that could contribute to the success of WQT programs.
• Optimize models for the administration of WQT programs to conform to the Paper Reduction Act and investigate
opportunities to minimize transaction costs.
• Provide protocol for minimum rules of engagement to specify interaction between programs and organizations.
Develop guidelines based on science and lessons learned.
• Develop a simple, but rigorous audit plan to formally track WQT and BMP implementation and compliance.
• Assess federal and state compliance-based and voluntary programs to control NPS nutrient loads and evaluate
program performance, participation levels, and overall success. Develop recommendations for how to improve NPS
participation in WQT and quantitatively track existing BMPs in TMDL settings. Currently, the level of NPS regula-
tion and enforcement shifts WQT from being a true market and forces buyers to provide some other incentive
(e.g., financial compensation, improved property) to encourage participation of NPSs.
• Perform additional research on gaming risks and how watershed management plans in general and WQT programs
specifically can be designed to significantly increase the potential cost of this compliance strategy.
• Investigate the regulatory feasibility of sharing liability between PS, NPS, and/or a third party, and the impact that
may have on entry into the WQT market.
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12.0 References
2nd National Water Quality Trading Conference, held May 23-25, 2006 in Pittsburgh, PA, http://www.envtn.org/WQT-
conf_agenda.htm.
Allen, R., and M.A.Taylor (Allen & Taylor), 2000, Incentive-Based Solutions to Agricultural Environmental Problems: Re-
cent Developments in Theory and Practice, Journal of Agricultural and Applied Economics, 32,2 (August 2000):221-
134, Southern Agricultural Economics Association. Date accessed: 12/06/05.http://ideas.repec.0rg/a/jaa/jagape/
v32y2000i2p221-34.html.
Andersen, D.C., J.J. Sartoris, J.S. Thullen, and PG. Reusch, 2003, The effects of bird use on nutrient removal in a
constructed wastewater-treatment wetland, Wetlands, 23(2): 423-435.
Anderson, S.J., 2000, Appendix A: Tar-Pamlico River Basin, In Cross Cutting Analysis of Trading Programs: Nine Case
Studies Appendices A-l. Prepared for the National Academy of Public Administration. Retrieved Dec. 9, 2005 from
http://www.napawash.org/ pc_economy_environment/epa0601 .pdf.
Arheimer B. and H.B. Wittgren, 2002, Modelling Nitrogen Removal in Potential Wetlands at the Catchment Scale, Eco-
logical Engineering, 19(1): 63-80.
Armstrong, W, 1964, Oxygen diffusion from the roots of some British bog plants, Nature 204:801-802.
Atlas, R.M. and R. Bartha, 1981, Microbial Ecology: Fundamentals and Application, Addison-Wesley, Reading, MA.
Bass, K., 2000, Evaluation of a Small In-Stream Constructed Wetland in North Carolina's Coastal Plain, Masters Thesis,
North Carolina State University, Biological and Agricultural Engineering Department, Raleigh, North Carolina.
Bavor, H.J., C.M. Davies, and K. Sakadevan, 2001, Stormwater treatment: do constructed wetlands yield improved pol-
lution management performance over a detention pond system? Water Science and Technology, 44:11 -12.
Belmont, M.A., E. Cantellano, S.Thompson, M.Williamson, A. Sanchez, and C.D. Metcalfe, 2004, Treatment of domestic
wastewater in a pilot-scale natural treatment system in central Mexico, Ecological Engineering, 23(4-5) 299-311.
Bennett, B. and R. Gannon (Bennett & Gannon), 2004, Updatesto Stormwater BMP Efficiencies, Memorandum to Local
Programs, Neuse and Tar-Pamlico Stormwater Rules, NC Division of Water Quality, September 8.
Bojcevska, H. 2005, Hydraulic tracer study in a free-water surface flow constructed wetland system treating sugar factory
wastewater in Western Kenya, IFM/Department of Biology, Bowden, W.B., 1987, The biogeochemistry of nitrogen
in freshwater wetlands, Biogeochemistry 4:313-348.
Braskerud, B.C., 2002, Factors affecting nitrogen retention in small constructed wetlands treating agricultural nonpoint
source pollution, Ecological Engineering, 18(3) 351-370.
Breen, PR, 1990, A mass balance method for assessing the potential of artificial wetlands for wastewater treatment,
Water Research. 24(6) 689-697.
Breetz, H.L., K. Fisher-Vanden, L. Garzon, H. Jacobs, K. Kroetz, and R. Terry, 2004, Water Qual-
ity Trading and Offset Initiatives in the U.S.: A Comprehensive Survey, Dartmouth College, Hanover, NH,
www.dartmouth.edu/~kfv/waterqualitytradingdatabase.pdf.
Brookhart, M., 2003, Watershed permitting in North Carolina (Powerpoint presentation), presented at the
National Forum on Water Quality Trading, Chicago, IL, July 22-23, 2003, retrieved Dec 12, 2005 from
www.epa.gov/owow/watershed/trading/brookhart.ppt.
Brown, M.T., 1988, A simulation model of hydrology and nutrient dynamics in wetlands, Computers, Environment and
Urban Systems, 12(4): 221-237.
Cerezo, R.G., M. L. Suarez, and M. R. Vidal-Abarca, 2001, The performance of a multi-stage system of constructed wet-
lands for urban wastewater treatment in a semiarid region ofSE Spain, Ecological Engineering, 16(4): 501-517.
Chague-Goff, C., M.R. Rosen, and P. Eser, 1999, Sewage effluent discharge and geothermal input in a natural wetland,
Tongariro Delta, New Zealand, Ecological Engineering, 12 (22): 149-170.
100
-------
Cherry Creek Basin Water Quality Authority, 2003a, Cherry Creek Reservoir Watershed Plan 2003.
Cherry Creek Basin Water Quality Authority, 2003b, Trading Program Guidelines.
Cherry Creek Basin Water Quality Authority, 2003c, Summary Cherry Creek Basin Water Quality Authority Trading
Program.
Cherry Creek Basin Water Quality Authority, 2005, 2004 Annual Report On Activities, March 31.
Collentine, D., 2003, Including nonpoint sources in a water quality trading permit program: Diffuse Pollution Confer-
ence, Section 2a: Policy and Socio-economics, Dublin, 6 p.
Cooper, PR, and B.C. Findlater (eds.), 1990, Constructed Wetlands in Water Pollution Control, Proceedings of the
International Conference on the Use of Constructed Wetlands in Water Pollution Control, Cambridge, UK, 24-28
September, WRc, Swindon, Wiltshire, UK.
Copeland, C., 2005, Resources, Science, and Industry Division Water Quality: Implementing the Clean Water Act,
CRS Issue Brief for Congress Order Code IB89102, Library of Congress, Washington D.C.
Crites, R.W, R.C. Watson, and C.R. Williams, 1995, Removal of metals in constructed wetlands. In: Proceedings of
WEFTEC 1995, Miami, FL. Water Environment Federation, Alexandria, VA.
Crumpton, W, 2006, Assessing the State of Science: Geographic and Landscape Scale Considerations, Presentation
from Research Planning Conference on Wetlands and Water Quality Trading, February 14-16, Chicago, IL, USERA,
Ada, OK.
Davis, S.E. Ill, C. Corronado-Molina, D.L. Childers, and J.W Day, Jr., 2003, Temporally dependent C, N, and P dy-
namics associated with the decay of Rhizophora mangle L. leaf litter in oligotrophic mangrove wetlands of the
Southern Everglades Aquatic Botany. 75(3): 199-215.
Day, J.W. Jr., J.Y. Ko, J. Rybczyk, D. Sabins, R. Bean, G. Berthelot, C. Brantley, L. Cardoch, W. Conner, J.N. Day, A.J.
Englande, S. Feagley, E. Hyfield, R. Lane, J. Lindsey, J. Mistich, E. Reyes, and R. Twilley, 2004, The Use of Wet-
lands in the Mississippi Delta for Wastewater Assimilation: a Review, Ocean & Coastal Management 47:671-691.
de Groot, R.S., 1994, Environmental functions and the economic value of natural ecosystems, pages 151-168 in Invest-
ing in Natural Capital: The Ecological Economics Approach to Sustainability, Island Press, Washington, DC.
De Wit, M., 1999, Nutrient uxes in the Rhine and Elbe basins, PhD thesis, Faculty of Geographical Sciences, Utre-
cht University, Netherlands Geographical Studies:259, The Netherlands.
De Wit, M., 2001, Nutrient uxes at the river basin scale. I: the PolFlow model, Hydrological Processes 15:743-759.
DeAlessi, M., 2003, Removing Muck WITH Markets: A Case Study on Pollutant Trading for Cleaner Water, Policy
Brief to Reason Foundation, August 1, 2003, Retrieved November 26, 2005 from: http://rppi.org/pb24.pdf.
DeBusk, WF, 1999, Nitrogen Cycling in Wetlands. University of Florida, Institute of Food and Agricultural Science,
Gainesville, FL.
DeLaney, T.A., 1995, Benefits to Downstream Flood Attenuation and Water Quality As a Result of Constructed Wet-
lands in Agricultural Landscapes. American Farmland Trust, http://www.aftresearch.org/researchresource/cae-
pubs/delaney.html (January 2006).
Dierberg, F.E., T.A. DeBusk, S.D. Jackson, M.J. Chimney, and K. Pietro, 2002, Submerged aquatic vegetation-based
treatment wetlands for removing phosphorus from agricultural runoff: response to hydraulic and nutrient loading.
Water Research 36:1409-1422.
D0rge, Jesper, 1994, Modelling Nitrogen Transformations in Freshwater Wetlands: Estimating Nitrogen Retention and
Removal in Natural Wetlands in Relation to their Hydrology and Nutrient Loadings. Ecological Modelling. 75-76:
409-420
EDS, 1998, DUFLOW, a microcomputer package for simulation of one-dimensional unsteady ow and water quality
in open channel systems, Leidchendam, The Netherlands.
Elias, J.M., E.S. Filho, and E. Salati, 2001, Performance of constructed wetland system for public water supply, Water
Science and Technology 44:11-12.
Environmental Credits Generated Through Land-Use Changes: Challenges and Approaches held March 8-9, 2006 in
Baltimore, MD, http://www.envtn.org/LBcreditsworkshop/agenda.htm.
Environmental Trading Network, 2003, Water Quality Trading Nonpoint Credit Bank Model. National Association of
Conservation Districts, http://www.envtn.org/docs/TradingBankModel-CreditScenarios.doc (January 2006).
Environomics, 1999, A Summary of U.S. Ef uent Trading and Offset Projects, prepared for USERA by Environomics,
Bethesda, MD, http://www.epa.gov/owow/watershed/trading/traenvrn.pdf, (December 2005).
101
-------
Epibare, R., E. Heidig, and D.W. Gibson, 1993, Prevention of Mosquito Production at an Aquaculture Wastewater
Reclamation Plant in San Diego, California using an innovative sprinkler system. In: Bulletin of the Society for
Vector Ecology 18(1):40-44.
Ewel, K.C. and H.T. Odum (eds), 1984, Cypress Swamps. University of Florida Press, Gainesville, FL.
Faeth, P., 2000, Fertile Ground: Nutrient Trading's Potential to Cost-effectively Improve Water Quality, World Resourc-
es Institute, Washington, DC.
Fang, F and K.W Easter, 2003, Pollution Trading to Offset New Pollutant Loadings-A Case Study in the Minnesota
River Basin, presented at American Agricultural Economics Association Annual Meeting, Montreal, Canada, July
27-30.
Faulkner, S.P and C.J. Richardson, 1989, Physical and chemical characteristics of freshwater wetland soils, In: Con-
structed Wetlands for Wastewater Treatment - Municipal, Industrial, and Agricultural. Lewis Publishers, Chelsea,
Ml.
Feierabend, J.S. 1989, Wetlands: the lifeblood of wildlife, In: D.A. Hammer (ed.) Constructed Wetlands for Wastewater
Treatment, Municipal, Industrial and Agricultural. Lewis Publishers, Chelsea, Ml.
Fisher, J. and M.C. Acreman, 2004, Wetland nutrient removal: a review of the evidence, Hydrology and Earth System
Sciences 8(4):673-685.
Fraser, L.H., S. M. Carty, and D. Steer, 2004, A test of four plant species to reduce total nitrogen and TP from soil
leachate in subsurface wetland microcosms, Bioresource Technology. 94(2): 185-192.
Gannon, R., 2003, WQC Item no. 3 NCEMC Item no. 03-38 Request for Approval of Local Nitrogen Strategies Tar-
Pamlico Agriculture Rule: A Report to the NC Environmental Management Commission from the Tar-Pamlico
Basin Oversight Committee, October 8-9, retrieved Dec. 5, 2005 from: http://h2o.enr.state.nc.us/nps/EMCRpt-
LocStrtgsl 0-03prn.pdf.
Gannon, R., 2005, North Carolina Division of Water Quality, Telephone interview, December 9.
Gannon, R., 2005a, NCEMC Agenda Item No. 0511: Tar-Pamlico Nutrient Sensitive Waters Implementation Strategy:
Phase III. North Carolina Division of Water Quality. Apr. 14, 2005. Retrieved Dec. 5, 2005 from http://h2o.enr.
state.nc.us/nps/documents/Phl IIAgreementFinal4-05.pdf
Gannon, R., North Carolina Division of Water Quality, 2005b, Pollutant Trading in North Carolina's River Basins: Tar-
Pamlico and Neuse River Basins, Presentation to the University of Pennsylvania IES Seminar December 7.
Gannon, R., North Carolina Division of Water Quality, 2006, Telephone interview on February 1.
Gathumbi, S.M., PJ. Bohlen, and D.A. Graetz, 2005, Nutrient enrichment of wetland vegetation and sediments in sub-
tropical pastures, Soil Science Society of America Journal 69:539-548.
Gerke, S., L.A. Baker, and Ying Xu, 2001, Nitrogen Transformations in a Wetland Receiving Lagoon Ef uent: Sequen-
tial Model and Implications for Water Reuse, Water Research. 35(16): 3857-3866.
Goforth, G.F., 2001, Surmounting the engineering challenges of Everglades restoration, Water Science and Technol-
ogy 44:11-12.
Gowda, PH., A.D. Ward, D.A. White, D.B. Baker, and T.J. Logan, 1998, Modelling drainage practice impacts on the
quantity and quality of stream ows for an agricultural watershed in Ohio, In: Proceedings of the Seventh Interna-
tional Symposia of the ASAE, Orlando, FL.
Gray, S. J. Kinross, P. Read, and A. Marland, 2000, The nutrient assimilative capacity of maerl as a substrate in con-
structed wetland systems for waste treatment, Water Research. 34(8): 2183-2190.
Hamersley, M.R., B.L. Howes, D.S. White, S. Johnke, D. Young, S.B. Peterson, and J.M.Teal, 2001, Nitrogen balance
and cycling in an ecologically engineered septage treatment system, Ecological Engineering. 18(1): 61-75.
Hammer D.A., 1996, Creating Freshwater Wetlands, Second Edition, CRC-Press; 2 edition (October 31, 1996).
Hammer, D.A., 1989, Constructed Wetlands for Wastewater Treatment - Municipal, Industrial, and Agricultural, Lewis
Publishers, Chelsea, Ml.
Hammer, D.A., 1992, Creating Freshwater Wetlands, Lewis Publishers, Inc. Boca Raton, FL.
Heimlich, R., 2003, Agricultural Resources and Environmental Indicators, 2003, Agriculture Handbook No. (AH722),
Economic Research Service, U.S. Department of Agriculture. February, 2003, downloaded on January 27, 2006
from http://www.ers.usda.gov/publications/arei/ah722/dbgen.htm.
Hench, K.R. G.K. Bissonnette, A.J. Sexstone, J.G. Coleman, K. Garbutt, and J.G. Skousen, 2003, Fate of physical,
chemical, and microbial contaminants in domestic wastewater following treatment by small constructed wetlands,
Water Research. 37(4): 921-927.
102
-------
Hough, P. and L. Hall, 2005, Background: The History and Status of Wetland Mitigation Banking and Water Quality
Trading, Ecosystem Marketplace, the Katoomba Groups,
http://www2.eli.org/pdf/wqtforum/presentations/Hough.Hall.pdf (December 2005).
Huang, J., R.B. Reneau, Jr., and C. Hagedorn, 2000, Nitrogen Removal in Constructed Wetlands Employed to Treat
Domestic Wastewater. Water Research; 34(9): 2582-2588.
Huett, D.O., S.G. Morris, G. Smith, and N. Hunt, 2005, Nitrogen and phosphorus removal from plant nursery runoff in
vegetated and unvegetated subsurface ow wetlands, Water Res. 39(14):3259-72.
Huisman, J., North Carolina Division of Water Quality, 2006, Telephone interview on February 1, 2006.
Humboldt University, 2000, Constructed Treatment Wetland System Description and Performance Database
http://firehole.humboldt.edu/wetland/twdb.html (January 2006).
Hunt, PG. and M.E. Poach, 2001, State of the art for animal wastewater treatment in constructed wetlands, Water
Science and Technology 44 (11-12):19-25.
Hunt, WF. and B.A. Doll, (Hunt and Doll), 2000, Designing Stormwater Wetlands for Small Watersheds. North Caro-
lina Cooperative Extension, North Carolina State University, Retrieved Dec. 5, 2005 from http://www.neuse.ncsu.
ed u/SWwetla nds. pdf
Idaho Clean Water Cooperative, 2000, Draft bylaws, http://yosemite.epa.gov/r10/ oi.nsf/Webpage/
Lower+Boise+River+Ef uent+Trading+Demonstration+Project/$FILE/AppA2.pdf (December 2005).
Idaho Department of Environmental Quality, 1999, Lower Boise River TMDL, Subbasin Assessment, Total Maximum
Daily Loads (Revised September 29, 1999), http://www.deq.state.id.us/water/data_reports/surface_water/tmdls/
boise_river_lower (December 2005).
Idaho Department of Environmental Quality, 2001, 1st Annual Status Report, Lower Boise Ef uent Trading Demon-
stration Project, http://www.deq.state.id.us/water/data_reports/surface_water/tmdls/boise_river_lower/boise_river_
lower_ef uent_status01 .pdf (December 2005).
Idaho Department of Environmental Quality, 2002, 2nd Annual Status Report, Lower Boise Ef uent Trading Demon-
stration Project, http://www.deq.state.id.us/water/data_reports/surface_water/tmdls/boise_river_lower/boise_river_
lower_ef uent_status02.pdf (December 2005).
Idaho Department of Environmental Quality, 2003, Draft Pollutant Trading Guidance, http://www.deq.state.id.us/water/
prog_issues/waste_water/pollutant_trading/pollutant_trading_guidance_entire.pdf (December 2005).
Idaho Department of Environmental Quality, 2005a, Surface Water: Lower Boise River Subbasin Assessment and
Total Maximum Daily Loads, Idaho Department of Environmental Quality, Boise, ID, http://www.deq.state.id.us/
water/data_reports/surface_water/tmdls/boise_river_lower/boise_river_lower.cfm (December 2005).
Idaho Department of Environmental Quality, 2005b, Phosphorus Total Daily Maximum Load for Lower Boise River,
Lower Boise River Water Quality Plan, http://www.lbrwqp.boise.id.us/phos_tmdl.htm (December 2005).
Idaho Department of Environmental Quality, 2005c, Environmental Laws Affecting the Lower Boise River, Lower
Boise River Water Quality Plan, http://www.lbrwqp.boise.id.us/env_laws.htm#WAG (December 2005).
Idaho Soil Conservation Commission, 2002, Best Management Practices (BMP) List for the Lower Boise River Pollu-
tion Trading Program, http://www.envtn.org/docs/boise_bmp_manual_DRAFT.doc (December 2005).
Jaksch, J, 2000, Appendix D, Rahr Malting. In. Kerr, R.L., S.J. Anderson, and J. Jaksch. 2000. Nine Case Studies,
Appendices A-l, Kerr, Greiner, Anderson & April, and Battelle Pacific Northwest Division, http://www.napawash.
org/pc_economy_environment/learning_texts.html .
Jardinier, N., G. Blake, A. Mauchamp, and G. Merlin, 2001, Design and performance of experimental constructed
wetlands treating coke plant ef uents. Water Science and Technology 44:11 -12.
Jennings, G. and D. Osmond, 2005, Lessons Learned from the Neuse River Basin Education Program, presented at
13th National Nonpoint Source Monitoring Workshop, Raleigh, North Carolina, September 18-22, http://www.bae.
ncsu.edu/programs/extension/wqg/nmp_conf/presentations.html.
Jing, S., Y. Lin, T Wang, and D. Lee, 2002, Microcosm wetlands for wastewater treatment with different hydraulic load-
ing rate and macrophytes, Journal of Environmental Quality 31:690-696.
Johansson, A.E., A.K. Klemedtsson, L. Klemedtsson, and B.H. Svensson, 2003, Nitrous oxide exchanges with the
atmosphere with the atmosphere of a constructed wetland treating wastewater: Parameters and implications for
emission factors, Tellus Ser. B Chem. Phys. Meteorol. 55B(3), 737-750.
Johnasson, R.C., PH. Gowda, D.J. Mulla, and B.J. Dalzell, 2004, Metamodelling phosphorus best management prac-
tices for policy use: a frontier approach, Agricultural Economics 30:63-74.
103
-------
Johnston, C.A., 1991, Sediment and nutrient retention by freshwater wetlands: effects on surface water quality, Criti-
cal Review in Environmental Control 12:491-565
Johnston, C.A., N.E. Detenbeck, and G.J. Niemi, 1990, The cumulative effect of wetlands on stream water quality and
quantity: a landscape approach, Biogeochemistry 10:105-141.
Kadlec, R.H. and D.E. Hammer, 1988, Modeling Nutrient Behavior, in Ecological Modelling, Volume 40, Issue 1, Janu-
ary 1988, Pages 37-66.
Kadlec, R.H. and R.L. Knight, 1996, Treatment Wetlands, Lewis Publishers, Boca Raton, FL.
Kadlec, R.H., 2000, The inadequacy of first-order treatment wetland models, Ecological Engineering 15:105-119.
Kennedy, T, 2003, Trend Analysis of Nutrient Loading in the Tar-Pamlico Basin. Memorandum to Michelle Woolfolf,
NC Division of Water Quality Planning Branch. http://h2o.enr.state.nc.us/nps/TrendGrimesland91-02prn.pdf.
Kerr, R.L., S.J. Anderson, and J. Jaksch, 2000, Cross Cutting Analysis of Trading Programs: Nine Case Studies Ap-
pendices A-l. Prepared for the National Academy of Public Administration. Retrieved Dec. 9, 2005 from http://
www.napawash.org/ pc_economy_environment/epa0601 .pdf.
Kieser & Associates, 2004, Ecosystem Multiple Markets, A White Paper (Draft), The Environmental Trading Network,
April, 2004.
Kieser, M.S. and A.F. Fang, 2005, Water Quality Trading in the United States: An Overview, Ecosystem Mar-
ketplace, the Katoomba Groups, http://ecosystemmarketplace.com/pages/ article.news.php?component_
id=3954&component_version_id=5593&language_id=12 , December 2005.
Kieser, M.S. and A.F. Fang, no date, Economic and Environmental Benefits of Water Quality Trading - An Over-
view of U.S. Trading Programs, http://ecosystemmarketplace.com/pages/article.news.php?component_
id=3954&component_version_id=5593&language_id=12 , December 2005.
King D. and P. Kuch, 2003, Will Nutrient Credit trading Ever Work? An Assessment of Supply and Demand Problems
and Institutional Obstacles: Environmental Law Reporter, 33 ELR 10352, 5-2003.
King, D.M., 2005, Crunch Time for Water Quality Trading, Choices Magazine, 20(1): 71-75.
Kirk, C.J.D,. and H.J. Kronzucker, 2005, The Potential for Nitrification and Nitrate Uptake in the Rhizosphere of Wet-
land Plants: A Modelling Study, Annals of Botany, 96(4):639-646.
Klomjek, P. and S. Nitisoravut, 2005, Constructed treatment wetland: a study of eight plant species under saline con-
ditions Chemosphere, Volume 58, Issue 5, Pages 585-593.
Klopatek, J.M., 1978, Nutrient dynamics of freshwater riverine marshes and the role of emergent macrophytes, In:
Freshwater Wetlands: Ecological Processes and Management Potential, R.E. Good, D.F Whigham, and R.L.
Simpson, eds., Academic Press, New York, NY.
Knight, R.L., 1992, Ancillary benefits and potential problems with the use of wetlands for nonpoint source pollution
control, Ecological Engineering 1:97-113.
Knight, R.L., V.W.E. Payne Jr., R.E. Borer, R.A. Clarke Jr., and J.H. Pries, 2000, Constructed wetlands for livestock
wastewater management Ecological Engineering, Volume 15, Issues 1-2, Pages 41-55, June.
Koberg, S., 2006, Water Quality Resource Conservationist, Idaho Association of Soil Conservation Districts, Boise,
Idaho, Personal Communication, February 1.
Kramer, J., 2000, Analysis of phosphorus control cost and effectiveness for point and nonpoint sources in the Fox-
Wolf Basin, Resource Strategies, lnc.http://www.rs-inc.com/FWB2K_Final_Report.pdf (December 2006).
Kuschk, P., A. Wieszner, U. Kappelmeyer, E. Weiszbrodt, M. Kastner, and U. Stottmeister, 2003, Annual cycle of nitro-
gen removal by a pilot-scale subsurface horizontal ow in a constructed wetland under moderate climate, Water
Research, Volume 37, Issue 17, pages 4236-4242, October.
Kydland, F.E. and E.G. Prescott, 1977, Rules rather than discretion: The inconsistency of optimal plans: Journal of
Political Economy, 85(3), 473-491.
Langergraber, G., 2001, Development of a simulation tool for subsurface ow constructed wetlands, In: Wiener Mit-
teilungen 169, Vienna, Austria, p. 207.
Langergraber, G., 2003, Simulation of subsurface ow constructed wetlands-results and further research needs,
Water Sci Technology; 48(5):157-66.
Langergraber, G., 2005, The role of plant uptake on the removal of organic matter and nutrients in subsurface ow
constructed wetlands: a simulation study, Water Sci Technol.; 51(9):213-23.
Lee, G.F, E. Bentley, and R. Amundson, 1975, Effects of marshes on water quality, In: Coupling of Land and Water
Systems, A.D. Hasler, Ed., Springer-Verlag, New York, NY.
104
-------
Leitch, J.A. and P. Frigden, 2000, Functions and Values of Prairie Wetlands: Economic Realities: Department of Agri-
cultural Economics, North Dakota State University, 8 p.
Lemly, A.D., H.M. Ohlendorf, (Lemly and Ohlendorf), 2002, Regulatory Implications of Using Constructed Wetlands to
Treat Selenium-Laden Wastewater, Ecotoxicology and Environmental Safety 52, 46-56 (2002).
Lin, Y, S. Jing, T. Wang, and D. Lee, 2002, Effects of macrophytes and external carbon sources on nitrate removal
from groundwater in constructed wetlands • ARTICLE, Environmental Pollution, Volume 119, Issue 3, Pages 413-
420, October.
Lord, B., 2005, Neuse River Education Team, North Carolina State University, telephone interview, 12/9/2005.
Luederitz, V, E. Eckert, M. Lange-Weber, A. Lange, and R.M. Gersberg, 2001, Nutrient removal efficiency and re-
source economics of vertical ow and horizontal ow constructed wetlands • ARTICLE Ecological Engineering,
Volume 18, Issue 2, Pages 157-171.
Mankin, K.R. and R.P Fynn, 1996, Modeling individual nutrient uptake by plants: relating demand to microclimate,
Agric. Syst., 50: 101-114.
Matheson, F.E.; M.L. Nguyen, A.B. Cooper, T.R Burt, and D.C. Bull, 2002, Fate of 15N-nitrate in unplanted, planted and
harvested riparian wetland soil microcosms, Ecological Engineering, Volume 19, Issue 4 Pages 249-264.
Mayo, A.W and T. Bigambo, 2005, Nitrogen transformation in horizontal subsurface ow constructed wetlands I:
Model development • ARTICLE Physics and Chemistry of the Earth, Parts A/B/C, Volume 30, Issues 11-16,
Pages 658-667.
McBride, G.B. and C.C. Tanner, 1999, Modelling biofilm nitrogen transformations in constructed wetland mesocosms
with uctuating water levels Ecological Engineering, Volume 14, Issues 1-2, Pages 93-106, September.
Mclsaac, G.F., M.B. David, G.Z. Gertner, and D.A. Goolsby, 2002, Relating Net Nitrogen Input in the Mississippi River
Basin to Nitrate Flux in the Lower Mississippi River: A Comparison of Approaches, Journal of Environmental
Quality 31:1610-1622.
Meuleman, A.F, M.R. van Logtestijn, G.B.J. Rijs, and J.T.A. Verhoeven, 2003, Water and mass budgets of a vertical-
ow constructed wetland used for wastewater treatment, Ecological Engineering, 20(1): 31-44.
Michigan Department of Environmental Quality, 2002, Water Quality Trading Rules Executive Summary, http://www.
michigan.gov/printerFriendly/0,1687,7-135-3313_3682_3719-14329-,00.html.
Mitsch, WJ. and J.G. Gosselink, 2000, Wetlands, 3rd Edition, John Wiley & Sons, Inc., New York, NY.
Moshiri, G.A. (ed.), 1993, Constructed Wetlands for Water Quality Improvement, CRC Press, Boca Raton, FL.
Mourad, D. and M. van der Perk, 2004, Modelling nutrient uxes from diffuse and point emissions to river loads: the
Estonia part of the transboundary Lake Peipsi/Chudskoe drainage basin (Russia/Estonia/Latvia), Water Science
and Technology 49:21-28.
MPCA, 1997, Fact Sheet - Rahr Malting Company "trading" permit.
MPCA, 2005, National Pollutant Discharge Elimination System (NPDES) and State Disposal System (SDS) Permit
MNG420000: Minnesota River Basin.
MPCA, Minnesota Department of Agriculture, and Water Resources Center at the University of Minnesota, 2003,
State of the Minnesota River: Summary of Surface Water Quality Monitoring, 2003.
MPCA, Undated, Fact Sheet - Phosphorus in the Minnesota River, Minnesota River Basin.
Murphy, S., 2005. Information on Water Quality Parameters, USGS Water Quality Monitoring, BASIN Project, City of
Boulder, CO http://bcn.boulder.co.us/basin/data/BACT/info/ (January 2006).
Mwanuzi, F, H. Aalderink, and L. Mdamo, 2003, Simulation of pollution buffering capacity of wetlands fringing the
Lake Victoria, Environment International 29:95-103.
National Forum on Synergies Between Water Quality Trading and Wetlands Mitigation Banking held July 11-12, 2005
in Washington, DC, http://www2.eli.org/research/wqt_main.htm.
Natural Resources Conservation Service, 2001, The phosphorus index, Agronomy Technical Note 26 (revised), Port-
land, OR.
NCDENR, 1998, Neuse River Basinwide Water Quality Plan, http://h2o.enr.state.nc.us/basinwide/Neuse/ neuse_wq_
management_plan.htm
NCDENR, 2001, Phase II of the Total Maximum Daily Load forTotal Nitrogen to the Neuse River Estuary, North Car-
olina, North Carolina Department of Environment and Natural Resources, Division of Water Quality, December.
105
-------
NCDWQ, 1999, Tar-Pamlico River Basinwide Water Quality Plan (July 1999), North Carolina Division of Water Qual-
ity, Retrieved Dec. 5, 2005 from http://h2o.enr.state.nc.us/basinwide/tarpam_wq_management_plan.htm,
NCDWQ, 2005, Nonpoint Source Management Program: Tar-Pamlico Nutrient Strategy website, Date accessed:
12/06/05, http://h2o.enr.state.nc.us/nps/tarpam.htm.
Negotiation Team (The Chesapeake Bay Program Nutrient Trading Negotiation Team), 2001, Fundamental Nutrient
Trading Principles and Guidelines. EPA 903-B-01-001 CBP/TRS 254/01, March.
Nelson, S.M., R. Roline, J.S. Thullen, J.J. Sartoris, J.E. Boutwell, 2000, Invertebrate Assemblages And Trace Element
Bioaccumulation Associated With Constructed Wetlands, Wetlands, pp. 406-415.
Neuse River Education Team, 2004, Wetland Project Teaches Students how to Protect our Water Supply, Neuse River
Education Team, North Carolina State University website, Viewed on 12/05/2005 at: http://www.neuse.ncsu.edu/
neuse_letters/winter2004/story2.htm.
Neuse River Education Team, Neuse Education Team Impacts: Agricultural Impacts 2: Novel Nursery. Neuse River
Education Team, North Carolina State University website. Viewed on 12/05/2005 at http://www.neuse.ncsu.edu/
impact2b.pdf.
Newport, Alan, 2004, An Environmental Big Stick, National Hog Farmer, PRIMEDIA Business Magazines and Media,
Inc., March 15.
Nixon, S.W and V Lee, 1986, Wetland and Water Quality, Wetlands Research Program, Tech. Rept. Y-86-2, US. Army
Engineers Waterway Experiment Station, Vicksburg, MS.
Omernik, J.M., 1977, Nonpoint Source-Stream Nutrient Level Relationships: A Nationwide Study, USERA 600/3-79-
105, Corvallis Environmental Research Laboratory, U.S. USERA, Corvallis, OR.
Payne, V.W.E., and R.L. Knight, 1997, Constructed wetlands for treating animal wastes, Section I: Performance,
design, and operation, p. 1-48. In Payne Engineering and CH2M Hill (ed.) Constructed wetlands for animal waste
treatment, USEPA Spec. Publ., Gulf of Mexico Program, Nutrient Enrichment Committee, USEPA, Washington,
DC.
Persson, J., 2005, The use of design element in wetlands, Nordic Hydrology 36(2):113-120.
Persson, J., and H.B. Wittgren, 2004, How hydrological and hydraulic conditions affect performance of ponds, Eco-
logical Engineering 21:259-269.
Persson, J., N.L.G. Somes, and T.H.F Wong, 1999, Hydraulic efficiency of constructed wetlands and ponds, Water
Science and Technology 40 (3): 291-300.
Poach, M.E., PG. Hunt, M.B. Vanotti, K.C. Stone, T.A. Matheny, M.H. Johnson, and E.J. Sadler, 2003, Improved
nitrogen treatment by constructed wetlands receiving partially nitrified liquid swine manure • ARTICLE Ecological
Engineering, Volume 20, Issue 2, Pages 183-197, May.
Priya, S., and R. Shibasaki, 2001, National spatial crop yield simulation using CIS-based crop production model,
Ecological Modelling 136(2-3):113-129.
Raffini, E., and M. Robertson, 2005, Water Quality Trading: What Can We Learn From 10 Years of Wetland Mitigation
Banking? National Wetlands Newsletter, vol. 27, no. 4. Environmental Law Institute, Washington D.C., USA, July-
August, Downloaded on January 30, 2006 from http://www2.eli.org/pdf/wqtforum/RafRob05.pdf.
Raisin, G.W and D.S. Mitchell, 1995, The use of wetlands for the control of nonpoint source pollution, Water Science
and Technology, 32(3)177-186.
Reddy, K.R., E.M. D'Angelo, and T.A. DeBusk, 1989, Oxygen transport through aquatic macrophytes: the role in
waster water treatment, Journal of Environmental Quality 19:261-267.
Reed, S. and R. Brown, 1991, Constructed Wetland Design the Second Generation, 64th WPCF Annual Conference &
Exposition.
Research Triangle Institute and USEPA, Office of Wetlands, Oceans, and Watersheds, Watershed Management Sec-
tion (Research Triangle Institute & USEPA), Undated, TMDL Case Study: Tar-Pamlico Basin, North Carolina, Total
Maximum Daily Load Program, USEPA Office of Water. Site viewed on 11/26/05, http://www.epa.gov/owow/tmdl/
cs10/cs10.htm.
River Basin Center, 2003, A Framework for Trading Phosphorus Credits in the Lake Allatoona Watershed, River Basin
Center Institute of Ecology, University of Georgia. Athens, GA http://www.rivercenter.uga.edu/research/nutrient/
trading.htm (January 2006).
Romero, J.A., H. Brix, and FA. Comin, 1999, Interactive effects of N and P on growth, nutrient allocation and NH4
uptake kinetics by Phragmites australis. Aquatic Botany. 64: 369-380.
106
-------
Ross and Associates Environmental Consulting, Ltd., 2000, Lower Boise River Effluent Trading Demonstration Proj-
ect: Summary of Participant Recommendations for Trading Framework, http://www.deq.state.id.us/water/data_re-
ports/surface_water/tmdls/boise_river_lower/boise_river_lower_ef uent_report.pdf (December 2005).
Sakadevan, K., and H.J. Bavor, 1999, Nutrient removal mechanisms in constructed wetlands and sustainable water
management, Water Science Technology 40:121-128.
Schary, C., 2005, Water Quality Trading, Office of Management and Information, U.S. Environmental Protection
Agency, Region 10, Seattle, WA, Personal Communication, December 15, 2005.
Schubauer-Berigan, J.P, 2005, Draft Research Initiative to Evaluate the Role of Wetlands in a National Water Quality
Trading Program Version 3, Office of Research and Development, National Risk Management Research Labora-
tory, USERA, Cincinnati, OH.
Schulz, C., J. Gelbrecht, and B. Rennert, 2003, Treatment of rainbow trout farm ef uents in constructed wetland with
emergent plants and subsurface horizontal water ow, Aquaculture, Volume 217, Issues 1-4, 17,Pages 207-221,
March.
Shabman, L. and P. Scodari (Shabman & Scodari), 2004, Past, Present, and Future of Wetlands Credit Sales, Dis-
cussion Paper 04-48, Resources for the Future, Washington DC (not peer reviewed), Retrieved Nov. 26, 2005
from http://www.rff.org/documents/rff-dp-04-48.pdf.
Shirmohammadi, A., B. Ulen, L.F. Bergstrom, and WG. Knisel, 1998, Simulation of nitrogen and phosphorus leaching
in a structured soil using GLEAMS and a new submodel, "PARTLE," Transactions of the ASAE, 41(2):353-360.
Simunek, J., M. Senja, and M.T. van Genuchten, 1999, The HYDRUS-2D software package for simulating the two-di-
mensional movement of water, heat, and multiple solutes in variably saturated media, International Ground Water
Modeling Center, Colorado School of Mines, Golden, Colorado, USA, Version 2.0, IGWMC-TPS-53.
Slather, J.H., 1989, Ancillary benefits of wetlands constructed primarily for wastewater treatment, In: D.A. Hammer
(ed.) Constructed Wetlands for Wastewater Treatment, Municipal, Industrial and Agricultural, Lewis Publishers,
Chelsea, Ml.
Stadmark, J. and L. Leonardson, 2005, Emissions of greenhouse gases from ponds constructed for nitrogen removal,
Ecological Engineering 25:542-551.
Stavins, R.N. and B.W Whitehead, 1996, The Next Generation of Market-Based Environmental Policies, Discussion
Paper 97-10 Prepared for Environmental Reform: The Next Generation Project, Daniel Esty and Marian Chertow,
editors, Yale Center for Environmental Law and Policy.
Stedman, S. and J. Hanson, 2005, Wetlands, Fisheries & Economics in the South Atlantic Coastal States, NOAA
Wetlands Web Site.
Stein, O.R., PB. Hook, J.A. Biederman, WC. Allen, and D.J. Borden, 2003, Does batch operation enhance oxidation
in subsurface constructed wetlands? Water Sci Technol. 48(5):149-56.
Stermole, F.J. and J. Stermole, 1993, Economic Evaluation and Investment Decision Methods, 8th ed., Investments
Evaluations Corp.
Stockdale, E.G., 1991, Freshwater Wetlands, Urban Stormwater, and Nonpoint Pollution Control: A Literature Review
and Annotated Bibliography, 2nd Ed. WA Dept. of Ecology, Olympia, WA.
Szabo A, A. Osztoics, F Szilagyi, 2001, Natural wastewater treatment in Hungary, Water Sci Technol. 44(11-12):331-
8.
Szb'gi, A.A., PG. Hunt, E.J. Sadler, and D.E. Evans, 2004, Characterization of Oxidation-Reduction Processes in
Constructed Wetlands for Swine Wastewater Treatment, Applied Engineering in Agriculture, Vol. 20(2): 189-200.
Szb'gi, A.A., PG. Hunt, F.J. Humenik, K.C. Stone, J.M. Rice, and E.J. Sadler, 1994, Seasonal dynamics of nutrients
and physico-chemical conditions in a constructed wetland for swine wastewater treatment, ASAE Paper #94-
2602.
Tanner, C.C., 2001 a, Growth and nutrient dynamics of soft-stem bulrush in constructed wetlands treating nutrient-rich
wastewaters, Wetl. Ecol. Manag. 9, 49-73.
Tanner, C.C., 2001 b, Plants as ecosystem engineers in subsurface- ow treatment wetlands, Water Science and Tech-
nology, 44:11-12.
Tanner, C.C., J.P.S. Sukias, and M.P Upsdell, 1998, Substratum phosphorus accumulation during maturation of
gravel-bed constructed wetlands, Water Science and Technology, 40(3): 647-659.
Tanner, C.C., M.L. Nguyen, and J.P.S. Sukias, 2005, Nutrient removal by a constructed wetland treating subsurface
drainage from grazed dairy pasture, Agriculture, Ecosystems & Environment, Volume 105, Issues 1-2, Pages
145-162.
107
-------
Thullen, J.S., J.J. Sartoris, and W.E.Walton, 2002, Effects of vegetation management in constructed wetland treat-
ment cells on water quality and mosquito production, Ecological Engineering, Volume 18, Issue 4, 1 Pages 441-
457, March.
Tietenberg, T., 2001, "Introduction," Pp. xi-xxviii in Emissions Trading Programs. Volume I. Implementation and Evolu-
tion. Aldershot, England: Ashgate Publishing Limited.
US Army Corps of Engineers, Omaha Division, Undated, Website reviewed December 2005, http://www.nwo.usace.
army.mil/html/Lake_Proj/TriLakes/TLCCDam.htm .
US Department of Agriculture, 2000, Constructed wetlands bibliography. Ecological Sciences Division of the Natural
Resources Conservation Service and the Water Quality Information Center at the National Agricultural Library,
http://www.nal.usda.gov/wqic/Constructed_Wetlands_all/index.html (January 2006).
USDA, 2005, Secretary's Memorandum, Subject: USDA Roles in Market-Based Environmental Stewardship.
USDA, 2006, 2007 Farm Bill Theme Papers: Conservation and the Environment, June.
USERA, 1993a, Subsurface Flow Constructed Wetlands For Wastewater treatment: A Technology Assessment.
USEPA 832-R-93-008. Office of Water, Washington, DC.
USEPA, 1993b, Constructed Wetlands for Wasterwater Treatment and Wildlife Habitat: 17 Case Studies, USEPA 832-
R-93-005, Office of Wastewater Management, Washington, DC.
USEPA, 1994, Wetlands Treatment Database (North American Wetlands for Water Quality Treatment Database), R.H.
Kadlec, R.L. Knight., S.C. Reed, and R.W Rubles (eds.), USEPA/600/C-94/200, Office of Research and Develop-
ment, Cincinnati, OH.
USEPA, 1996, Draft TMDL Program Implementation Strategy, Total Maximum Daily Load Program, December 20.
USEPA, 1999, Free Water Surface Wetlands for Wasterwater Treatment: A Technology Assessment, USEPA 832-S-
99-001, Office of Wastewater Management, Washington, DC.
USEPA, 2000a, Guiding Principles for Constructed Treatment Wetlands: Providing for Water Quality and Wildlife Habi-
tat, USEPA 843-B-00-003, Office of Wetlands, Oceans, and Watersheds, Washington, DC.
USEPA, 2000b, Manual: Constructed Wetlands Treatment of Municipal Wastewaters. USEPA/625/R-99/010, Office of
Research and Development, Cincinnati, OH.
USEPA, 2002a, The Twenty Needs Report: How Research Can Improve the TMDL Program, EPA841-B-02-002, July
2002.
USEPA, 2002b, Watershed based permitting case study: final permit, Neuse River Compliance Association, Retrieved
on Dec 12, 2005 from http://www.epa.gov/npdes/pubs/wq_casestudy_factsht11.pdf.
USEPA, 2002c, Lower Boise River Ef uent Trading Demonstration Project, http://yosemite.epa.gov/r10/oi.nsf/
5d8e619248feObd88825650f00710fbc/bb77984122984abd8825696c00793442?OpenDocument (January 2006).
USEPA, 2003a, Final Water Quality Trading Policy, Office of Water, Water Quality Trading Policy, January 13, 2003,
http://www.epa.gov/owow/watershed/trading/finalpolicy2003.html (December 2005).
USEPA, 2003b, National Pollutant Discharge Elimination System (NPDES), Office of Wastewater Management,
http://cfpub.epa.gov/npdes/ (December 2005).
USEPA, 2003c, Introduction to the Clean Water Act, USEPA, Watershed Academy Web, March 2003, Unpublished
website information retrieved on January 30, 2006 from http://www.epa.gov/watertrain/cwa/index.htm.
USEPA, 2004, Wetlands and the West Nile Virus, Office of Water Quality, Washington, DC, USEPA 843-F-04-010, re-
trieved from http://www.epa.gov/owow/wetlands/pdf/WestNile.pdf.
USEPA, 2005a, National Management Measures to Protect and Restore Wetlands and Riparian Areas for the Abate-
ment of Nonpoint Source Pollution, USEPA 841-B-05-003, Office of Water, Washington, DC.
USEPA, 2005b, Polluted Runoff (Nonpoint Source Pollution): Clean Water Act Section 319, USEPA, Office of Water,
October, 2005, Unpublished website information retrieved on January 30, 2006 from http://www.epa.gov/owow/
nps/cwact.html.
USEPA, 2005c, Section 319 Nonpoint Source Program Success Story: North Carolina, Tar-Pamlico Basin Agricultural
Management Strategy, USEPA, Office of Water, EPA 841-F-05-0048, retrieved on Decembers, 2005 from http://
www.epa.gov/nps/Success319/state/nc_tar.htm.
USEPA, Undated, Watershed-Based Permitting Case Study: Final Permit, Rahr Malting Company National Pollutant
Discharge Elimination System and State Disposal System Permit No. MN003191, Fact Sheet #5.
van der Peijl, M.J. and J.T.A. Verhoeven, 1999, A model of carbon, nitrogen and phosphorus dynamics and their inter-
actions in river marginal wetlands, Ecological Modelling, Volume 118, Issues 2-3, Pages 95-130, June 15.
108
-------
van der Peijl, M.J., M.M.R van Oorschot, and J.T.A. Verhoeven, 2000, Simulation of the effects of nutrient enrichment
on nutrient and carbon dynamics in a river marginal wetland, Ecological Modelling, Volume 134, Issues 2-3, 30
October 2000, Pages 169-184.
Walton, WE. and J.A. Jiannino, 2005, Vegetation management to stimulate denitrification increases mosquito abun-
dance in multipurpose constructed treatment wetlands, Journal of the American Mosquito Control Association
21(1):22-27.
Water Quality Control Commission, 2001, Regulation No. 72: Cherry Creek Reservoir Control Regulation 5 CCR
1002-72, Colorado Department of Public Health and Environment, First adopted November 6, 1985, last amend-
ment effective September 30, 2001.
Wayland, K.G., D.W Hyndman, D. Boutt, B.C. Pijanowski, and D.T. Long, 2002, Modelling the impact of historical
land uses on surface-water quality using groundwater ow and solute-transport models, Lakes and Reservoirs:
Research and Management, Volume 7, Issue 3, Page 189-199, September.
Wegehenkel, M., 2000, Test of a modeling system for simulating water balances and plant growth using various dif-
ferent complex approaches, Ecol. Model, 129: 39-64.
Wetzel, R.G, 2001, Fundamental processes within natural and constructed wetland ecosystems: short-term versus
long-term objectives, Water Science and Technology 44:11-12.
White, J.R. and K.R. Reddy, 2003, Nitrification and Denitrification Rates of Everglades Wetland Soils along a Phos-
phorus-Impacted Gradient, Journal of Environmental Quality 32:2436-2443.
Whitehead, J.C., 1992. Measuring Use Value from Recreation Participants, Southern Journal of Agricultural Econom-
ics 24(2): 113-119, December.
Wong, T.H.F and W.F. Geiger, 1997, Adaptation of wastewater surface ow wetland formulae for application in con-
structed stormwater wetlands, Ecological Engineering 9:187-202.
Woodward, R.T and R. Kaiser, 2002, Market Structures for U.S. Water Quality Trading, 24 Rev. of Agric. Econ. 373.
Woodwell, G.M. and D.E. Whitney, 1977, Flax Pond ecosystem study: exchange of phosphorus between as salt
marsh and the coastal waters of Long Island Sound, Marine Biology 41:1-6.
Wossink, A. and B. Hunt (Wossink & Hunt), 2003b, An Evaluation of Cost and Benefits of Structural Stormwater Best
Management Practices, North Carolina Cooperative Extension Service, Fact Sheet, November, Retrieved Dec. 5,
2005 from: http://www2.ncsu.edU/unity/lockers/users/g/gawossin/ stormwaterBMPFactsheet.pdf
Wossink, A. and B. Hunt, 2003a, The Economics of Structural Stormwater BMPs in North Carolina, WRRI Research
Report Number 344. Retrieved Dec. 5, 2005 from http://www.ag-econ.ncsu.edu/faculty/wossink/outreach.html
Wulliman, J., Undated, Cherry Creek Basin Phosphorus Control Projects, Muller Engineering Company.
Zentner, J., 1995, Meeting Flood Control and Wetland Needs, Public Works.
109
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Appendix A
Annotated Bibliography
111
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#
1
2
3
4
5
6
7
8
9
Title
Managing the Brisbane River and
Moreton Bay: An Integrated Research/
Management Program to Reduce Im-
pacts on an Australian Estuary.
Biomass Production and NPK Reten-
tion in Macrophytes from Wetlands of
the Tingitan Peninsula
Hydrologic Performance of a Large-
Scale Constructed Wetland: The Ever-
glades Nutrient Removal Project
Ecological Issues Related to N Deposi-
tion to Natural Ecosystems: Research
Needs
Nutrient Partitioning in a Clay-based
Surface Flow Wetland
Hydrologic Regime Controls Soil
Phosphorus Fluxes in Restoration and
Undisturbed Wetlands
Framework for Surface Water Quality
Management on a River Basin Scale:
Case Study of Lake Iseo, Northern Italy
South Nation Watershed Phosphorus
Algorithm Report Phase II
Proceedings of a Conference on Wet-
lands for Wastewater Treatment and
Resource Enhancement
AAA Author
Abal, E.G., WC.
Dennison, and PF.
Greenfield
Abdeslam Ennabili,
Mohammed Ater and
Michel Radoux
Abtew, Wossenu and
Tim Bechtel
Adams, Mary Beth
Adcock, P.W., G.
L. Ryan and P. L.
Osborne
Aldous, Allison, Paul
McCormick, Chad
Ferguson, Sean Gra-
ham, and Chris Craft
AI-Khudhairy, D. H.
A., A. Bettendrof-
fer, A. C. Cardoso,
A. Pereira, and G.
Premazzi
Allaway, Chris (B.Sc.)
Allen, G.H.and R.H.
Pub.
Date
2001
Sep-98
Aug-01
Jun-03
1995
Jun-05
Jul-01
Jan-03
1988
Type
Paper
Conference
Proceeding
Paper Abstract
Abstract
Paper
Paper
Publisher
Water Sci Technol.
2001 ;43(9):57-70. PMID:
11419140
Aquatic Botany; 62(1): 45-
56 Sept 1 1998
Wetlands Engineering &
River Restoration 2001 ,
Proceedings of the 2001
Wetlands Engineering &
River Restoration Confer-
ence, August 27-31 ,
2001, Reno, Nevada.
Section 36, Chapter 1 .
Environment Interna-
tional; 29(2-3): 189-199.
June 2003.
Water Science and Tech-
nology; 32(3): 203-209.
1995.
Restoration Ecology;
13(2): 341. June 2005.
Lakes and Reservoirs:
Research and Manage-
ment: 6(2): 1 03-1 1 5. July
2001
South Nation Conserva-
tion Clean Water Com-
mittee
Humbolt Sate University,
Arcata CA
Comments
This report describes results of an interdisciplinary study of
Moreton Bay to examine the link between sewage and diffuse
loading with environmental degradation. The study includes
examination of runoff and deposition of fine-grained sediments,
sewage-derived nutrient enrichment, blooms of a marine cyano-
bacterium, and seagrass loss. The study framework illustrates
a unique integrated approach to water quality management
whereby scientific research, community participation and the
strategy development were done in parallel with each other.
This collaborative effort resulted in a water quality management
strategy which focuses on the integration of socioeconomic and
ecological values of the waterways.
This paper summarizes the hydrologic performance, mass bal-
ance and treatment efficiency of one of the largest constructed
wetlands in the world.
Many wetland restoration projects occur on former agricultural
soils that have a history of disturbance and fertilization, mak-
ing them prone to phosphorus (P) release upon coding. We
conclude that maintaining moist soil is the means to minimize
P release from recently coded wetland soils. Alternatively, pro-
longed coding provides a means of liberating excess labile P
from former agricultural soils while minimizing continued organic
P mineralization and soil subsidence.
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#
10
11
12
13
14
15
16
17
18
19
20
21
22
23
Title
Treatment of Domestic Wastewater by
Subsurface Flow Constructed Wetlands
in Jordan
South Nation River Conservation
Authority: What has 57 years of Wa-
tershed Management and Multi-Million
Dollar Watershed Plans Taught Us?
The Effects of Bird Use on Nutrient
Removal in a Constructed Wastewater-
Treatment Wetland
Temporal and spatial development of
surface soil conditions at two created
riverine marshes
Temporal Export of Nitrogen from a
Constructed Wetland: In uence of
Hydrology and Senescing Submerged
Plants
Modelling Nitrogen Removal in Poten-
tial Wetlands at the Catchment Scale
Oxygen diffusion from the roots of
some British bog plants
SWRRB: A Basin Scale Simulation
Model for Soil and Water Resources
Management
Latitudinal characteristics of below- and
above-ground biomass of Typha: a
modelling approach
Microbial Ecology: Fundamentals and
Application
Denitrification, N20 and C02 uxes
in rice-wheat cropping system as af-
fected by crop residues, fertilizer N and
legume green manure
Update on the Tradable Loads Program
in the Grassland Drainage Area
Treatment of Wastewater by Natural
Systems
Denitrification in Constructed Free-
water Surface Wetlands: I. Very High
Nitrate Removal Rates in a Macrocosm
Study
AAA Author
Al-Omari, Abbas and
Manar Fayyad
American Society
of Agricultural and
Biological Engineers,
St. Joseph, Michigan
www.asabe.org
Andersen, Douglas
C., James J. Sartoris,
Joan S. Thullen, and
Paul G. Reusch
Anderson, C.J., WJ.
Mitsch, R.W Nairn
Ann-Karin Thoren,
Catherine Legrand,
and Karin S. Tonder-
ski
Arheimer, Berit and
Hans B. Wittgren
Armstrong, W
Arnold, J.G., J.R.Wil-
liams, A.D. Nicks, and
N.B. Sammons
Asaeda, T, D.N. Hai,
J. Manatunge, D. Wil-
liams, and J. Roberts
Atlas, R.M. and R.
Bartha
Aulakh, M.S., T.S.
Khera, J.W Doran,
and K.F. Bronson
Austin, S.
Ayaz, Selma C. and
Liitfi Akca
Bachand, Philip A.M.
and Alex J. Home
Pub.
Date
May-03
2004
Sep-02
Nov-
Dec-05
Dec-04
Jul-02
1964
1990
Aug-05
1981
Dec-01
Aug-99
Jan-01
Sep-99
Type
Abstract
Paper
Publisher
Desalination; 155(1): 27-
39. May 30, 2003.
American Society of
Agricultural and Biological
Engineers, St. Joseph,
Michigan, www.asabe.org
Wetlands; 23(2): 423-425.
September 2002.
Journal of Environmental
Quality; 34(6): 2072-2081.
Nov-Dec 2005.
Ecological Engineering;
23(4-5): 233-239. Dec 30,
2004.
Ecological Engineering;
19(1): 63-80. July 2002.
Nature 204:801 -802.
2004
Texas A&M Univ. Press.
College Station, TX.
Annals of Botany; 96(2):
299-31 2. Aug 2005.
Addison-Wesley, Read-
ing, MA.
Biology and Fertility of
Soils; 34(6): 375-389. Dec
2001.
Environment Interna-
tional; 26(3): 189-195.
January 2001.
Ecological Engineering;
14(1 -2): 9-1 5. September
1999.
Comments
http://asae.frymulti.com/abstract.asp?aid=16399&t=2
This case study supports the concept that a constructed
wetland can be designed both to reduce nutrients in municipal
wastewater and to provide habitat for wetland birds.
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#
24
25
26
27
28
29
30
31
32
33
34
Title
Denitrification in Constructed Free-
water Surface Wetlands: II. Effects of
Vegetation and Temperature
Holding the Line: Tampa Bay's Coop-
erative Approach to Trading
Nutrients and Zooplankton Composi-
tion and Dynamics in Relation to the
Hydrological Pattern in a Confined
Mediterranean Salt Marsh (NE Iberian
Peninsula)
Nitrogen mineralization processes
of soils from natural saline-alkalined
wetlands, Xianghai National Nature
Reserve, China
Spatial variability of nitrogen in soils
from land/inland water ecotones
Spatial Distribution Characteristics of
Organic Matter and Total Nitrogen of
Marsh Soils in River Marginal Wetlands
Introduction to Nonpoint Source Pollu-
tion in the United States and Prospects
for Wetland Use
Evaluation of a Small In-Stream Con-
structed Wetland in North Carolina's
Coastal Plain
Potential nitrification and denitrification
on different surfaces in a constructed
treatment wetland
GLTN Comments to the EPA on
Proposed Changes to the NPDES
Program
Growth of Phragmites australis (Cav.)
Trin ex. Steudel in Mine Water Treat-
ment Wetlands: Effects of Metal and
Nutrient Uptake
AAA Author
Bachand, Philip A.M.
and Alex J. Home
Bacon, E. and H.
Greening
Badosa, Anna, Dani
Boix, Sandra Brucet,
Rocio Lopez-Flores,
and Xavier D. Quin-
tana
Bai, J., W Deng, Q.
Wang, H.Chen, C.
Zhou
Bai, J., W. Deng.Y.
Zhu, and Q. Wang
Bai, Junhong, Hua
Ouyang, Wei Deng,
Yanming Zhu, Xuelin
Zhang, and Qinggai
Wang
Baker, Lawrence A.
Bass, Kristopher
Lucas
Bastviken, S.K., PG.
Eriksson, I. Mar-
tins, J.M. Neto, L.
Leonardson, and K.
Tonderski
Batchelor, David J.
(Chair)
Batty, Lesley C. and
Paul L. Younger
Pub.
Date
Sep-99
May-98
Feb-06
Aug-05
2004
Jan-05
Mar-92
Jun-05
Nov-
Dec-03
Jan-99
Nov-04
Type
Presentation
Master Thesis
Letter to Com-
ment Clerk
Publisher
Ecological Engineering;
14(1-2): 17-32. Septem-
ber 1999.
Watershed '98 - Moving
from Theory to Implemen-
tation. Denver, CO.
Estuarine, Coastal and
Shelf Science; 66(3-4):
513-522. February 2006.
Canadian Journal of Soil
Science; 85(3): 359-367.
Aug 2005.
Communications in Soil
Science and Plant Analy-
sis; 35(5-6): 735-749.
2004.
Geoderma; 124(1-2):
181-192. Jan 2005.
Ecological Engineering;
1(1-2): 1-26. March 1992.
Masters Thesis, North
Carolina State University,
Biological and Agricultural
Engineering Department,
Raleigh, North Carolina
Journal of Environmental
Quality; 32(6): 241 4-2420.
Nov-Dec 2003.
Environmental Pollution;
132(1): 85-93. Nov 2004.
Comments
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#
35
36
37
38
39
40
41
42
43
44
Title
Stormwater Treatment: Do Constructed
Wetlands Yield Improved Pollutant
Management Performance Over a
Detention Pond System?
Progress in the Research and Dem-
onstration of Everglades Periphyton-
based Stormwater Treatment Areas
Theoretical Consideration of Methane
Emission from Sediments
Incentives For Environmental Improve-
ment: An Assessment Of Selected
Innovative Programs In The States And
Europe
Feasibility of Using Ornamental Plants
(Zantedeschia aethiopica) in Sub-
surface Flow Treatment Wetlands to
Remove Nitrogen, Chemical Oxygen
Demand and Nonylphenol Ethoxylate
Surfactants: A Laboratory-Scale Study
Treatment of Domestic Wastewater in a
Pilot-scale Natural Treatment System in
Central Mexico
Updates to Stormwater BMP Efficien-
cies
Rainfall-runoff Modeling: The Primer
Quantification of oxygen release by
bulrush (Scirpus validus) roots in a
constructed treatment wetland
pH, redox, and oxygen microprofiles in
rhizosphere of bulrush (Scirpus validus)
in a constructed wetland treating mu-
nicipal wastewater
AAA Author
Bavor, H.J., C.M.
Davies, and K.
Sakadevan
Bays, J.S., R.L.
Knight, L. Wenkert, R.
Clarke, and S. Gong
Bazhin, N.M.
Beardsley, Daniel P.
Belmont, Marco A.
and Chris D. Metcalfe
Belmont, Marco A.,
Eliseo Cantellano,
Steve Thompson,
Mark Williamson,
Abel Sanchez, and
Chris D. Metcalfe
Bennett, Bradley and
Rich Gannon
Seven, K.J.
Bezbaruah, A.N. and
T.C.Zhang
Bezbaruah, A.N. and
T.C.Zhang
Pub.
Date
2001
2001
Jan-03
Aug-96
Dec-03
Dec-04
Sep-04
2001
Feb-05
Oct-04
Type
Report
Memo
Publisher
Water Science Technol-
ogy; 44(1 1 -1 2):565-70.
2001.
Water Science Technol-
ogy; 44(1 1 -1 2):1 23-30.
2001.
Chemosphere; 50(2):
191-200. Jan 2003.
Global Environmental
Management Initiative
Ecological Engineering;
21 (4-5): 233-247. Dec 31,
2003.
Ecological Engineering;
23(4-5): 299-31 1 . Dec 30,
2004.
Memorandum to Local
Programs, Neuse and
Tar-Pamlico Stormwater
Rules, NC Division of
Water Quality
John Wiley and Sons, Ltd.
Chichester, London
Biotechnology and Bioen-
gineering; 89(3): 308-318.
Feb 2005.
Biotechnology and Bio-
engineering; 88(1): 60-70.
Oct. 5, 2004.
Comments
This paper discussed a stationary theory of gas emission from
sedimentary (active) layers of wetlands, which takes into ac-
count methane generation in a sedimentary layer and its depth
dependence, and the solubility and the mobility of methane
molecules set by the methane diffusion coefficient.
http://www.ncbi. nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db
=PubMed&list_uids=1 2653291 &dopt=Abstract
http://www.gemi.org/! DE_003.pdf
Memo notifying the Neuse and Tar-Pamlico Stormwater
Programs of new nutrient removal efficiencies for Stormwater
BMPs.
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#
45
46
47
48
49
50
51
52
53
54
55
56
Title
Hydrological Simulation Program
- FORTRAN Version 12 User's Manual
N storage and cycling in vegetation
of a forested wetland: implications for
watershed in processing
Evaluation of Past and Potential Phos-
phorus Uptake at the Orlando Easterly
Wetland
The effects of varied hydraulic and
nutrient loading rates on water quality
and hydrologic distributions in a natural
forested treatment wetland
Nitrogen as a Regulatory Factor of
Methane Oxidation in Soils and Sedi-
ments
Hydraulic tracer study in a free-water
surface ow constructed wetland sys-
tem treating sugar factory wastewater
in Western Kenya
Pollutant Removal Capability of a Con-
structed Melaleuca Wetland Receiving
Primary Settled Sewage
Metabolism of Compounds with Nitro-
functions by Klebsiella pnuemoniae
Isolated from a Regional Wetland
Controlled drainage and wetlands to
reduce agricultural pollution: a lysimet-
ric study
The biogeochemistry of nitrogen in
freshwater wetlands
Nutrient Removal from Ef uents by
an Artificial Wetland: In uence of
Rhizosphere Aeration and Preferential
Flow Studied Using Bromide and Dye
Tracers
Salinity & Nutrient Trading in Australia
AAA Author
Bicknell, B.R., J.C.
Imhoff, J.L. Kittle, Jr.,
T.H. Jobes, and A.S.
Donigian, Jr.
Bischoff, J.M., P.
Bukaveckas, M.J.
Mitchell, and T. Hurd
Black, Courtney A.
and William R.Wise
Blahnik, T. and J.
Day, Jr.
Bodelier, Paul L. E.
and Hendrikus J.
Laanbroek
Bojcevska, H.
Bolton, Keith G.E.
and Margaret Gre-
enway
Boopathy, Ramaraj
and Earl Melancon
Borin, M., G. Bonaiti,
and L. Giardini
Bowden, WB.
Bowmer, Kathleen H.
Brady, Katy
Pub.
Date
2001
May-01
Dec-03
Mar-00
Mar-04
2005
Mar-99
Dec-04
Jul-Aug-
01
1987
May-87
3/16-
18/2004
Type
Presentation
Publisher
National Exposure Re-
search Laboratory. U.S.
Environmental Protection
Agency. Athens, GA.
Water, Air, and Soil Pol-
lution; 128(1 -2): 97-1 14.
May 2001 .
Ecological Engineering;
21 (4-5): 277-290. Dec 31,
2003.
Wetlands : the journal
of the Society of the
Wetlands Scientists. Mar
2000. v. 20(1) p. 48-61.
FEMS Microbiology Ecol-
ogy; 47(3): 265-277. Mar
1 5, 2004.
IFM/Department of
Biology, University of
Linkbping, Linkbping,
Sweden.
Water Science and Tech-
nology; 39(6): 199-206.
March 1999.
International Biodeteriora-
tion & Biodegradation;
54(4): 269-275. Dec 2004.
Journal of environmental
quality. July/Aug 2001 . v.
30 (4) p. 1330-1340.
Biogeochemistry 4:313-
348.
Water Research, Volume
21, Issue 5, May 1987,
Pages 591 -599
New South Wales
Environment Protection
Authority, Australia
Comments
This paper summarises and balances the data on the regula-
tory role of nitrogen in the consumption of methane by soils and
sediments with the intent of stimulating the scientific community
to embark on experiments to close the existing gap in knowl-
edge regarding the role of nitrogen in methan oxidation in soils
and sediments.
http://www.blackwell-synergy.eom/doi/abs/1 0.1 01 6/S01 68-
6496(03)00304-0
http://www.ifm. liu.se/~inuita/researchproposal_tracerstudy.doc
http://www.inece.org/emissions/brady.pdf
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#
57
58
59
60
61
62
63
64
65
Title
Factors Affecting Nitrogen Retention in
Small Constructed Wetlands Treating
Agricultural Non-Point Source Pollution
The impact of hydraulic load and
aggregation on sedimentation of soil
particles in small constructed wetlands
Restoration of Lake Borrevannet - Self-
purification of Nutrients and Suspended
Matter through Natural Reed-belts
A Mass Balance Method for Assessing
the Potential of Artificial Wetlands for
Wastewater Treatment
Water Quality Trading and Offset Initia-
tives in the U.S.: A Comprehensive
Survey*
A comparison of nutrient availability
indices along an ombrotophic-minero-
trophic gradient in Minnesota wetlands
Application of Wastewater to Wetlands
Nutrient Assimilative Capacity of an
Alluvial Floodplain Swamp
Gas Exchange through the Soil-at-
mosphere Interphase and through
Dead Culms of Phragmites australis
in a Constructed Reed Bed Receiving
Domestic Sewage
AAA Author
Braskerud, B.C.
Braskerud, B.C., H.
Lundekvam, and T
Krogstad
Rratli I I A QU-inla
Dlalll, J.L., rt. oKlpIc
and M Mielde
Breen, Peter F.
Breetz, Hanna L. and
Karen Fisher-Vanden,
Laura Garzon, Han-
nah Jacobs, Kailin
Kroetz, Rebecca
Terry
Bridgham, S.D., K.
Updegraff, and J.
Pastor
Brinson, M.M. and
F R Westall
Brinson, M.M., H.D.
Bradshaw, and E.S.
Kane
Brix, H.
Pub.
Date
Jan-02
Nov~
Dec-00
1999
Jun-90
Aug-04
Jan-
Feb-01
1983
Dec-84
Feb-90
Type
Paper
Report
Publisher
Ecological Engineering;
18(3): 351 -370. January
2002.
Journal of environmental
quality. Nov/Dec 2000. v.
29(6) p. 2013-2020.
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 325-332
Water Research, Volume
24, Issue 6, June 1990,
Pages 689-697
http://www.dartmouth.
edu/~kfv/waterqualitytrad-
ingdatabase.pdf
Soil Science Society of
America journal. Jan/Feb
2001. v. 65(1) p. 259-269.
Rept. #5, Water Research
Inst., Univ. of North Caro-
lina, Raleigh, NC
Journal of Applied Ecolo-
gy Vol.21, No. 3, p 1041-
1057, December, 1984.9
Fig, 2 Tab, 45 Ref. OWRT
project B-114-NC.
Water Research, Volume
24, Issue 2, February
1 990, Pages 259-266
Comments
This research was supported by the US Environmental Protec-
tion Agency and the Rockefeller Center at Dartmouth College.
Corresponding author: 6182 Steele Hall, Hanover, NH 03755;
phone: 603-646-0213; email: kfv@dartmouth.edu
Summarizes waterquality trading and offset initiatives in the
U.S., including state-wide programs and recent proposals. The
document provides background information on each program
and provides specific information on each program for the
following categories: trade structure (determination of credit,
trading ratios and other mechanisms to deal with uncertainty,
liabilities/penalties for non-complinace, approval process, ex
post-verification/auditing, machanisms for trade identifica-
tion and communication, market structure and types of trades
allowed); outcomes (types and volumes of trades that have
occured, adminiatrative costs, transaction costs, cost savings,
program goals achieved, program obstacles, MPS inolvement
and incentives to engage in trading, and other); and program/in-
formation references.
The capacity of the swamp for nutrient removal was highest for
nitrate, intermediate for ammonium, and lowest for phosphate.
Annual drydown of sediments would be required for sustained
ammonium removal in swamps with prolonged coding, as in
this case. It appears that swamps of this type could be man-
aged for inorganic nitrogen removal from sewage ef uent, but
their usefulness for tertiary treatment of phosphate is limited by
the capacity of sediments for phosphorus storage.
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#
66
67
68
69
70
71
72
73
74
75
76
77
Title
Treatment of Wastewater in the Rhi-
zosphere of Wetland PlantsuThe Root
Zone Method
Root-zone acidity and nitrogen source
affects Typha latifolia L. growth and up-
take kinetics of ammonium and nitrate
The Use of Vertical Flow Constructed
Wetlands for On-site Treatment of
Domestic Wastewater: New Danish
Guidelines
Denitrification in a Natural Wetland
Receiving Secondary Treated Ef uent
Watershed Permitting in North
Carolina: NPDES Permit NCC000001
Became Effective Jan 1 , 2003, Neuse
River Compliance Association
Watershed Permitting to Increase Ef-
ficiency and Facilitate Trading
Evaluating Constructed Wetlands
Through Comparisons with Natural
Wetlands
A Simulation Model of Hydrology and
Nutrient Dynamics in Wetlands
Nutrient Removal and Plant Biomass
in a Subsurface Flow Constructed
Wetland in Brisbane, Australia
Spatial variability of soil properties in
created, restored, and paired natural
wetlands
Treatment of Potato Processing Waste-
water with Engineered Natural Systems
Nitrogen and Phosphorus Removal by
Wetland Mesocosms Subjected to Dif-
ferent Hydroperiods
AAA Author
Brix, H.
Brix, H., K. Dyhr-Jen-
sen, and B. Lorenzen
Brix, Hans and Car-
los A. Arias
Brodrick, Stephanie
J., Peter Cullen and
W Maher
Brookhart, Morris
Brookhart, Morris
Brown, M.T.
Brown, MarkT.
Browning, K. and M.
Greenway
Bruland, G.L. and C.J.
Richardson
Burgoon, Peter S.,
Robert H. Kadlec and
Mike Henderson
Busnardo, Max J.,
Richard M. Gersberg,
Rene Langis, The-
resa L. Sinicrope and
Joy B. Zedler
Pub.
Date
1987
Dec-02
Dec-05
Apr-98
2003
Jul-03
1991
1988
2003
Jan-
Feb-05
1999
Dec-92
Type
Powerpoint
PowerPoint
Publisher
Water Sci Technol.,
19:107-118
Journal of experimental
botany. Dec 2002. v. 53
(379) p. 2441-2450.
Ecological Engineering;
25(5):491-500.Dec. 1,
2005.
Water Research, Volume
22, Issue 4, April 1988,
Pages 431 -439
Presented at the National
Forum on Water Quality
Trading, Chicago, IL, July
22-23, 2003. Retrieved
Dec. 12, 2005 from www.
epa.gov/owow/watershed/
trading/brookhart.ppt
EPA/600\3-91-058. EPA
Environmental Research
Lab., Corvallis, OR
Computers, Environment
and Urban Systems, Vol-
ume 12, Issue 4, 1988,
Pages 221 -237
Water Science Technol-
ogy. 2003;48(5): 183-9.
Soil Science Society of
America journal. 2005
Jan-Feb, v. 69, no. 1, p.
273-284.
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 21 1-21 5
Ecological Engineer-
ing, Volume 1 , Issue 4,
December 1992, Pages
287-307
Comments
2003 National Forum on Water Quality Trading
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#
78
79
80
81
82
83
84
85
86
Title
Riparian Alder Fens - Source or Sink
for Nutrients and Dissolved Organic
Carbon? - 2. Major Sources and Sinks
The Nitrogen Abatement Cost in
Wetlands
Economic Criteria for Using Wetlands
as Nitrogen Sinks Under Uncertainty
Defining the Mercury Problem in the
Northern Reaches of San Francisco
Bay and Designing Appropriate Regu-
latory Approaches
Pollutant Removal from Municipal Sew-
age Lagoon Ef uents with a Free-sur-
face Wetland
Proposed BMPs to be Applied in Trad-
ing Demonstration
Stream Assessment and Constructed
Stormwater Wetland Research in the
North Creek Watershed
Mechanisms of nutrient attenuation in a
subsurface ow riparian wetland
Effects of static vs. tidal hydrology on
pollutant transformation in wetland
sediments
AAA Author
Busse, Lilian B. and
Gunter Gunkel
Bystrom, Olof
Bystrom, Olof, Hans
Andersson, and Ing-
Marie Gren
California Environ-
mental Protection
Agency, San Fran-
cisco Bay Regional
Water Quality Control
Board
Cameron, Kimberly,
Chandra Madramoot-
oo, Anna Crolla, and
Christopher Kinsley
Carter, David L. (Ph.
D., CPAgSSc)
Carter, Melanie Dawn
Casey, R.E., M.D.
Taylor, S.J. Klaine
Catallo, WJ. and T
Junk
Pub.
Date
May-02
Sep-98
Oct-00
Jun-98
Jul-03
Feb-02
Mar-05
Sep-
Oct-01
Nov-
Dec-03
Type
Draft Staff
Report
BMP Proposal
Ph.D. Disser-
tation
Publisher
Limnologica - Ecology
and Management of In-
land Waters; 32(1): 44-53.
May 2002.
Ecological Economics,
Volume 26, Issue 3, 1
September 1998, Pages
321-331
Ecological Economics,
Volume 35, Issue 1 , Octo-
ber 2000, Pages 35-45
California Environmental
Protection Agency, San
Francisco Bay Regional
Water Quality Control
Board
Water Research; 37(1 2):
2803-2813. July 2003.
North Carolina State
University, Biological and
Agricultural Engineering,
URN:etd-031 42005-
1 03836
Journal of environmental
quality. Sept/Oct 2001 . v.
30 (5) p. 1732-1737.
Journal of environmental
quality. 2003 Nov-Dec, v.
32, no. 6, p. 2421-2427.
Comments
Based on stormwater runoff concerns, two constructed
stormwater wetlands (0.3 ac) were designed and installed on
the North Creek oodplain. The purpose of this study was to
measure stormwater treatment of sediment and nutrients during
initial stabilization (three months). Suspended sediment was
generated in both wetlands (W1 and W2) during the first two
weeks. Total suspended sediment loads were reduced in W2
but not in W1 by the end of the study. Nutrients (TKN, NH4,
NO3, TP) were all reduced in W1 throughout the study. Am-
monium and total phosphorus were generated in W2 throughout
the study. Differences between the two wetlands were due to
several variables, including the larger sediment and nutrient
concentrations entering W2. Polyacrylamide (PAM) was applied
to W1 only (15 Ib/ac) during hydromulching after construction.
The in uence of PAM was not clear, however, due to the numer-
ous different variables between the two wetlands.
http://www.lib.ncsu.edu/theses/available/etd-03142005-103836/
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#
87
88
89
90
91
92
93
94
95
96
Title
Developing an Ef uent Trading Pro-
gram to Address Nutrient Pollution in
the Providence and Seekonk Rivers
Master's Thesis
Effects of sediment deposition on fine
root dynamics in riparian forests.
The Number Catchment and Its
Coastal Area: From UK to European
Perspectives
The Practice of Watershed Protection:
Techniques for Protecting and Restor-
ing Urban Watersheds
The Performance of a Multi-stage Sys-
tem of Constructed Wetlands for Urban
Wastewater Treatment in a Semiarid
Region of SE Spain
Sewage ef uent discharge and
geothermal input in a natural wetland,
Tongariro Delta, New Zealand
The Use of Wetlands for Water Pollu-
tion Control
Water Quality Impacts of Climate and
Land Use Changes in Southeastern
Pennsylvania
Removal of Endocrine Disrupters by
Tertiary Treatments and Constructed
Wetlands in Subtropical Australia
Syntrophic-methanogenic associations
along a nutrient gradient in the Florida
Everglades
AAA Author
Caton, Patricia-Ann
Cavalcanti, G.G.,
B.C. Lockaby
Cave, R.R., L.
Ledoux, K. Turner, T
Jickells, J.E.Andrews,
and H. Davies
Center for Watershed
Protection
Cerezo, R. Gomez,
M.L. Suarez, and
M.R. Vidal-Abarca
Chague-Goff, C., M.
R. Rosen, and P. Eser
Chan, E., T.A. Bunsz-
tynsky, N. Hantzsche,
and Y.J. Litwin
Chang, Heejun
Chapman, H.
Chauhan, A., A.
Ogram, and K.R.
Reddy
Pub.
Date
May-02
May-
Jun-05
Oct-03
2000
Feb-01
Jan-99
1981
May-04
2003
Jun-04
Type
Paper
Paper
Publisher
Center for Environmental
Studies
Brown University
Soil Science Society of
America Journal. 2005
May-June, v. 69, no. 3, p.
729-737.
Sci Total Environ. 2003
Oct 1;31 4-31 6:31 -52. Re-
view. PMID: 14499525
Center for Watershed
Protection
Ecological Engineering;
16(4): 501 -51 7. February
1 , 2001 .
Ecological Engineering,
Volume 12, Number 1,
January 1999, pp. 149-
170(22).
EPA-600/S2-82-086. EPA
Municipal Environmental
Research Lab., Cincin-
nati, OH
The Professional Geogra-
pher, Volume 56, Issue 2,
Page 240-257, May 2004
Water Science Technol-
ogy. 2003;47(9): 151-6.
Applied and environ-
mental microbiology.
2004 June, v. 70, no.6, p.
3475-3484.
Comments
http://envstudies.brown.edu/Thesis/2002/caton/
includes multiple case studies at the following link: http://
envstudies.brown.edu/Thesis/2002/caton/FRAMES/
Case%20Study%20Frame.htm
This paper provides an overview of the current environmental
and socio-economic state of the Number catchment and coastal
zone, and broadly examines how socio-economic drivers affect
the uxes of nutrients and contaminants to the coastal zone,
using the driver-pressure-state-impact-response (DPSIR) ap-
proach.
Compilation by the Center for Watershed Protection of 150
articles on all aspects of watershed protection and represents
a broad interdisciplinary approach to restoring and maintain-
ing watershed health. Indexed for easy reference, this massive
volume is an invaluable reference for anyone interested in the
whys and hows of watershed protection practices. http://www.
cwp.org/PublicationStore/practice.htm
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#
97
98
99
100
101
102
103
Title
Chesapeake Bay Program Nutrient
Trading Fundamental Principles and
Guidslinss
Nutrient Trading in the Chesapeake
Bay Watershed, Public Workshop Pro-
ceedings (361 KB)
Nutrient Trading to Maintain the
Nutrient Cap in the Chesapeake Bay
Watershed (128KB)
Nutrient Trading for the Chesapeake
Bay (109KB)
Nutrient Trading in the Chesapeake
Bay Watershed, Public Comments
Summary (286 KB)
Endorsement of the Nutrient Trading
Fundamental Principles and Guide-
lines (555 KB)
Watershed Risk Analysis Model for
TVA's Holston River Basin
AAA Author
Chesapeake Bay
Program
Chesapeake Bay
Program
Chesapeake Bay
Program
Chesapeake Bay
Program
Chesapeake Bay
Program
Chesapeake Bay
Program
Chew, C.W, J. Herr,
R. A. Goldstsin,
F. J. Sagona,
K. E. Rylant, and
GF HaiiQpfQ
. c.. nuuocio
Pub.
Date
Mar-01
Apr-01
Dec-98
Apr-01
Apr-01
Mar-01
Jul-96
Type
Report
Report
Report
Report
Report
Executive
Council Action
Paper
Publisher
Chesapeake Bay Pro-
gram
Chesapeake Bay Pro-
gram
Chesapeake Bay Pro-
gram
Chesapeake Bay Pro-
gram
Chesapeake Bay Pro-
gram
Chesapeake Bay Pro-
gram
Water, Air, & Soil
Pollution (Histori-
cal Archive), Springer
Science+Business Media
B.V., Formerly Kluwer
Academic Publishers B.V.
ISSN: 0049-6979 (Paper)
1573-2932 (Online),
Volume 90, Numbers 1-2
Pages: 65 - 70
Comments
This document presents fundamental principles and guidelines
for nutrient trading in the Chesapeake Bay Watershed. This
document is not a regulation. Rather, it is intended to be used
on a voluntary basis as a guide for those Bay jurisdictions that
choose to establish nutrient trading programs. The document is
based on the Negotiation Team's comprehensive consideration
of numerous other trading programs and approaches, substan-
tial research, and corresponding lengthy negotiations.
The Chesapeake Bay Program completed a document de-
lineating nutrient trading guidelines entitled Nutrient Trading
Fundamental Principles and Guidelines - Draft and made this
document available to the public for review on September 8,
2000. A series of public meetings were held during the months
of September and October in a variety of locations around the
Chesapeake Bay watershed for the purpose of providing the
public with an explanation of the meaning and purpose of the
trading guidelines, and to give the public a chance to comment
on them. This document is a compilation of the public meeting
proceedings prepared for each of the 16 public meetings.
This is the workshop proceedings held on December 1 4, 1 998.
Its purpose, as delineated on the agenda (see Appendix I)
was to initiate a process to develop nutrient trading policies
and guidelines to achieve and maintain the Nutrient Cap in the
Chesapeake Bay Watershed.
This paper addresses the need for nutrient trading in the
Chesapeake Bay, the process to develop baywide guidelines,
and activities taken elsewhere in the Bay region.
Following the release of the Nutrient Trading Fundamental
Principles and Guidelines - Draft, sixteen public meetings
were collectively held throughout the watershed in each of the
signatory jurisdictions. All jurisdictions received numerous public
comments during the meetings as well as written comments
during the review period. This document is a summary of the
comments (both during the public meetings as well as those
written) received by the jurisdictions.
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#
104
105
106
107
108
109
110
111
112
113
114
Title
Seasonal changes of shoot nitrogen
concentrations and 15N/14N ratios in
common reed in a constructed wetland
Nutrient Trading Advocated to Improve
Water Quality
Dissolved organic nitrogen in contrast-
ing agricultural ecosystems
Dimensionless Volatilization Rate for
Two Pesticides in a Lake
Chemical Characteristics of Soils and
Pore Waters of Three Wetland Sites
Dominated by Phragmites australis:
Relation to Vegetation Composition and
Reed Performance
Role of Macrophyte Typha latifolia in
a Constructed Wetland for Wastewa-
ter Treatment and Assessment of Its
Potential as a Biomass Fuel
Role of macrophyte Typha latifolia in
a constructed wetland for wastewater
treatment and assessment of its poten-
tial as a biomass fuel
Nitrogen Pools and Soil Characteristics
of a Temperate Estuarine Wetland in
Eastern Australia
Water quality changes from riparian
buffer restoration in Connecticut
Thermal Load Credit Trading Plan at
Rock Creek and Durham wastewater
treatment facilities, OR, Clean Water
Services
Ammonium Oxidation Coupled to
Dissimilatory Reduction of Iron Under
Anaerobic Conditions in Wetland Soils
AAA Author
Choi, W.J., S.X.
Chang, H.M. Ro
Christen, K.
Christou, M., E.J. Av-
ramides, J.P Roberts,
D.L. Jones
Ciaravino, Giulio and
Carlo Gualtieri
Cikova, Hana, Libor
Pechar, t pan Husak,
Jan Kv t, Vaclav
Bauer, Jana Radova,
and Keith Edwards
Ciria, M.P., M.L. So-
lano, and P. Soriano
Ciria, M.P., M.L. So-
lano, P. Soriano
Clarke, PJ.
Clausen, J.C., K.
Guillard, C.M. Sig-
mund, and K.M. Dors
Clean Water Services
Clement, Jean-Chris-
tophe, Junu Shrestha,
Joan G. Ehrenfeld,
and Peter R. Jaffe
Pub.
Date
2005
Feb-02
Aug-05
Dec-01
Apr-01
Dec-05
Dec-05
Dec-85
Nov-
Dec-00
Oct-03
Dec-05
Type
Paper
Paper
Temperature
Management
Plan
Publisher
Communications in
Soil Science and Plant
Analysis. 2005, v. 36, no.
19-20, p. 2719-2731.
Environ Sci Technol. 2002
Feb 1 ;36(3):53A-54A.
PMID: 11871571
Soil Biology & Biochem-
istry. 2005 Aug., v. 37, no.
8, p. 1560-1563.
Lakes and Reservoirs:
Research and Manage-
ment, Volume 6, Issue 4,
Page 297-303, Dec 2001
Aquatic Botany; 69(2-4):
235-249. April 2001 .
Biosystems Engineering;
92(4): 535-544. Dec 2005.
Biosystems Engineering.
2005 Dec., v. 92, no. 4, p.
535-544.
Aquatic Botany, Volume
23, Issue 3, December
1 985, Pages 275-290
Journal of environmental
quality. Nov/Dec 2000. v.
29(6) p. 1751-1761.
Clean Water Services
Soil Biology and Bio-
chemistry; 37(12): 2323-
2328. Dec 2005.
Comments
No abstract available.
http://www.sciencedirect.eom/science/journal/1 53751 1 0
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#
115
116
117
118
119
120
121
Title
Search for the Northwest Passage: The
Assignation of NSP (non-point source
pollution) Rights in Nutrient Trading
Programs
Including Non-point Sources in a Water
Quality Trading Permit Program
Setting Permit Prices in a Transferable
Discharge Permit (TOP) System for
Water Quality Management
Including Non-point Sources in a Water
Quality Trading Permit
Economic Modelling of Best Manage-
ment Practices (BMPs) at the Farm
Level
Restoration of Wetlands from Aban-
doned Rice Fields for Nutrient Re-
moval, and Biological Community and
Landscape Diversity
Nitrogen Removal and Cycling in
Restored Wetlands Used as Filters of
Nutrients for Agricultural Runoff
AAA Author
Collentine, D.
Collentine, D.
Collentine, D.
Collentine, Dennis
Collentine, Dennis
Comin, Francisco A. ,
Jose A. Romero, Oli-
ver Hernandez, and
Margarita Menendez
Comin, Francisco
A., Jose A. Romero,
Valeria Astorga and
Carmen Garcia
Pub.
Date
2002
2005
2005
2003
2002
Jun-01
1997
Type
Paper
Paper
Paper
Publisher
Water Sci Technol;
45(9):227-34. 2002.
PMID: 12079107
Water Sci Technol; 51(3-
4):47-53. 2005. PMID:
15850173
Paper prepared for
presentation at the 99th
seminar of the EAAE
(European Association of
Agricultural Economists),
Copenhagen, Denmark
August 24-27, 2005
Diffuse Pollution Confer-
ence, Dublin 2003
In Steenvoorden, J.(ed.),
Agricultural Effects on
Ground and Surface
Waters. IAHS Publication
no. 273, 17-22.
Restoration Ecology,
Volume 9, Issue 2, Page
201-208, Jun2001
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 255-261
Comments
Paper from the Department of Economics, Swedish University
of Agricultural Sciences, Uppsala that analyzes the lack of
success in nutrient trading programs. Tradable permit solutions
are based on an assumption that the assignation of quantifi-
able rights to both point and nonpoint sources, based on some
predetermined ambient water quality measure, is possible. The
conclusion here is that there are significant features particular
to NSP that hinder the introduction of rights and significantly
decrease the utility of tradable permit solutions.
A paper that analyzes the problems with Transferable Dis-
charge Permit (TOP) systems and describes a composite
market system that may solve some of the common problems.
Problems with TOP systems are transaction costs and in the
case of non-point sources (NPS), undefined property rights. The
composite market design specifically includes agricultural NPS
dischargers and addresses both property rights and transaction
cost problems.
http://www.eaae2005.dk/CONTRIBUTED_PAPERS/S11_250_
Collentine.pdf
This paper proposes an innovative design for a Transferable
Discharge Permit (TOP) system, a composite market system.
The composite market design is a proposal for a TDF system,
which specifically includes agricultural non-point source (NPS)
dischargers and addresses both property rights and transaction
cost problems.
http://www.em/tn. org/docs/EMM_WHITE_PAPERApri!04.pdf
A number of experimental freshwater wetlands with different
ages since they were abandoned as rice fields, were used to
analyze the prospects of multipurpose wetland restoration for
such degraded areas. Nitrogen and phosphorus removal rate
of the wetlands was determined monthly during the coding
season to estimate their efficiency as filters to remove nutrients
from agricultural sewage. Both the temporal dynamics and
changes in the spatial pattern of land use cover during the last
20 years were determined from aerial photographs and field
analysis. All the wetlands appeared to be very efficient in the
removal of nitrogen and phosphorus exported from rice fields.
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#
122
123
124
125
126
127
128
129
130
131
132
133
Title
Comparison of Created and Natural
Freshwater Emergent Wetlands in Con-
necticut (USA)
Watershed Economic Incentives
Through Phosphorous Trading and Wa-
ter Quality, Innovations in Watershed
Stewardship
Reducing Diffuse Pollution through
Implementation of Agricultural Best
Management Practices: A Case Study
The Use of a Constructed Wetland for
the Amelioration of Elevated Nutrient
Concentrations in Shallow Groundwater
Anthropogenic landscapes and soils
due to constructed vernal pools
Use of Constructed Wetland to Protect
Bathing Water Quality
Constructed Wetlands in Water Pollu-
tion Control
Water Quality: Implementing the Clean
Water Act
Stormwater Permits: Status of
EPA's Regulatory Program
Response of biogeochemical indicators
to a drawdown and subsequent re ood
Introduction: Assessing Non-point
Source Pollution in the Vadose Zone
with Advanced Information Technolo-
gies
Removal of Municipal Solid Waste
COD and NH4-N by Phyto-reduction:
A Laboratory-scale Comparison of
Terrestrial and Aquatic Species at Dif-
ferent Organic Loads
AAA Author
Confer, S.R. and WA.
Niering
Conservation Authori-
ties of Ontario
Cook, M.G., PG.
Hunt, K.C. Stone and
J.H. Canterberry
Cook, Michael J. and
Robert O. Evans
Cook, T.D. and K.
Whitney
Coombes, C. and P. J.
Collett
Cooper, PR and B.C.
Findlater
Copeland, Claudia
(Resources, Science,
and Industry Division)
Copeland, Claudia
(Specialist in Re-
sources and Environ-
mental Policy
Resources, Science,
and Industry Division)
Corstanje, R. and
K.R. Reedy
Corwin, D.L., K.
League, and T.R.
Ellsworth
Cossu, Raffaell, Ketil
Haarstad, M. Cristina
Lavagnolo, and Paolo
Littarru
Pub.
Date
1992
Jun-05
1996
2001
2002
1995
1990
Apr-05
Feb-05
Nov-
Dec-04
1999
Feb-01
Type
Briefing
Briefing
Publisher
Wetlands Ecology & Man-
agement. 2(3):1 43-1 56
Conservation Authorities
of Ontario
Water Science and
Technology, Volume 33,
Issues 4-5, 1996, Pages
191-196
Paper number 012102,
2001 ASAE Annual Meet-
ing . @2001
Soil Survey Horizons. Fall
2002. v. 43 (3) p. 83-89.
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 149-1 58
IAWPRC. Pergamon
Press, Inc., Maxwell
House, NY
CRS Issue Brief for
Congress
Order Code IB89102
CRS Report for Congress
97-290 ENR
Journal of environmental
quality. 2004 Nov-Dec, v.
33, no. 6, p. 2357-2366.
pg. 1-20. In D.L. Corwin,
K. League, and T.R. Ells-
worth (ed.). Assessment
of non-point source pol-
lution in the vadose zone.
AGU. Washing ton, D.C.
Ecological Engineering;
16(4): 459-470. February
1 , 2001 .
Comments
http://www.ncseonline.org/nle/crsreports/05apr/IB89102.pdf
http://www.ncseonline.org/nle/crsreports/05Feb/97-290.pdf
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134
135
136
137
138
139
140
141
Title
Preliminary Investigation of an Inte-
grated Aquaculture-wetland Ecosystem
Using Tertiary-treated Municipal Waste-
water in Los Angeles County, California
Nutrient Removal from Eutrophic Lake
Water by Wetland Filtration
Rehabilitation of Freshwater Fisheries:
Tales of the Unexpected?
Forms and amounts of soil nitrogen
and phosphorus across a longleaf pine-
depressional wetland landscape
Removal of metals in constructed
wetlands
Comparative Changes in Water Quality
and Role of Pond Soil After Applica-
tion of Different Levels of Organic and
Inorganic Inputs
The in uence of organic carbon on
nitrogen transformations in five wetland
soils
Temporally Dependent C, N, and P
Dynamics Associated with the Decay
of Rhizophora mangle L. Leaf Litter in
Oligotrophic Mangrove Wetlands of the
Southern Everglades
AAA Author
Costa-Pierce, Barry
A.
Coveney, M.F., D.L.
Stites, E.F. Lowe,
L.E. Battoe, and R.
Conrow
Cowx, I. G., M. van
Zyll de Jong
Craft, C.B. and C.
Chiang
Crites, R.W, R.C.
Watson, and C.R.
Willams
Das, Pratap Chandra,
Subanna Ayyappan,
and Joykrushna Jena
Davidsson, T.E. and
M. Stahl
Davis, Stephen E.,
Ill, Carlos Corronado-
Molina, Daniel L.
Childers, and John W
Day, Jr.
Pub.
Date
Jul-98
Aug-02
Jun-04
Sep-
Oct-02
1995
Jun-05
May-
Jun-00
Mar-03
Type
Paper
Paper
Publisher
Ecological Engineering,
Volume 10, Issue 4, July
1 998, Pages 341 -354
Ecological Engineering;
19(2): 141-1 59. Aug 2002.
Fisheries Management
and Ecology, Volume 1 1 ,
Issue 3-4, Page 243-249,
Jun 2004
Soil Science Society of
America journal. Sept/Oct
2002. v. 66 (5) p. 1 71 3-
1721.
In: Proceedings of
WEFTEC 1995, Miami,
FL. Water Environment
Federation, Alexandria,
VI.
Aquaculture Research,
Volume 36, Issue 8, Page
785-798, Jun 2005
Soil Science Society of
America journal. May/
June 2000. v. 64 (3) p.
1129-1136.
Aquatic Botany; 75(3):
199-215. March 2003.
Comments
Changes in water parameters were studied in a yard experiment
for 7 weeks after application of cow dung, poultry manure, feed
mixture and inorganic fertilizers. To study the role of soil in the
mineralization process, each treatment was divided into two
groups - one with and the other without soil substrate. Higher
degree of changes in water parameters was observed at higher
input levels. Both organic amendment and inorganic fertilization
caused significant reduction (P<0.05) in dissolved oxygen and
increase in free CO2, dissolved organic matter, total ammo-
nia, nitrite, nitrate and phosphorus contents of water. Organic
inputs significantly decreased (P<0.05) water pH and increased
total alkalinity and hardness. In contrast, inorganic fertilization
caused a significant increase in pH; alkalinity and hardness
increased significantly in the presence of soil, but reduced in
its absence. In organic input, presence of soil substrate caused
significantly lower value of pH, dissolved oxygen, dissolved or-
ganic matter and phosphate-phosphorus and significantly higher
free CO2, alkalinity, hardness, ammonia, nitrite and nitrate
contents, compared with those in the absence of soil, revealing
enhanced microbial mineralization in the presence of soil.
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142
143
144
145
146
147
148
149
150
151
152
153
Title
The Use of Wetlands in the Mississippi
Delta for Wastewater Assimilation: A
Review
Nutrient uxes at the river basin scale.
I: the PolFlow model
Nutrient uxes in the Rhine and Elbe
basins
Nutrient Fluxes in the Po Basin
Removing Muck With Markets: A Case
Study on Pollutant Trading for Cleaner
Water
Nitrogen Cycling in Wetlands
Nonpoint Source Pollution Reductions-
Estimating a Tradable Commodity
Benefits to Downstream Flood Attenu-
ation and Water Quality As a Result of
Constructed Wetlands in Agricultural
Landscapes
A Screening of the Capacity of Louisi-
ana Freshwater Wetlands to Process
Nitrate in Diverted Mississippi River
Water
The Banking Experience: Environmen-
tal Performance Standards & Credit
Release
The Banking Experience: Environmen-
tal Performance Standards & Credit
Release
Economic Instruments for Water Pol-
lution
AAA Author
Day, J.W, Jr., Jae-
Young Ko, J. Ryb-
czyk, D. Sabins, R.
Bean, G. Berthelot, C.
Brantley, L. Cardoch
and W Conner, et al.
DeWit, M.
DeWit, M.
de Wit, M.and G.
Bendoricchio
DeAlessi, M.
DeBusk, WF.
Dedrick, Allen
DeLaney, T.A.
DeLaune, R.D., A.
Jugsujinda, J.L.West,
C.B. Johnson, and M.
Kongchum
Denisoff, Craig
Wildlands, Inc.
Denisoff, Craig
Wildlands, Inc.
Department for
Environment, Food &
Rural Affairs
Pub.
Date
2004
2001
1999
2001
Aug-03
1999
Jul-03
1995
Nov-05
7/11-
12/2005
7/11-
12/2005
Sep-99
Type
PhD thesis
Paper
Policy Brief
PowerPoint
Presentation
Presentation
Report
Publisher
Ocean & Coastal Man-
agement; 47(11-12):
671-691.2004.
Hydrological Processes
15:743-759.
Faculty of Geographical
Sciences, Utrecht Uni-
versity, Netherlands Geo-
graphical Studies:259.
The Netherlands.
Sci Total Environ. 2001
Jun12;273(1-3):1 47-61.
PMID: 11419598
Reason Foundations
University of Florida,
Institute of Food and
Agricultural Science,
Gainesville, FL.
American Farmland Trust
Ecological Engineering;
25(4): 31 5-321. Nov 1,
2005.
Audio Recording
PowerPoint Presentation
Department for Environ-
ment, Food & Rural
Affairs
Comments
http://rppi.org/pb24.pdf
2003 National Forum on Water Quality Trading
http://www.aftresearch.org/researchresource/caepubs/delaney.
html (January 2006).
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking. Describes
framework for establishing banks, including outlines of perfor-
mance standards, credit release, and monitoring. Draws on
information from existing mitigation banks in CA. - http://www2.
eli.org/research/wqtjnain.htm
http://www.defra.gov.uk/environment/water/quality/econinst2/in-
dex.htm
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#
154
155
156
157
158
159
160
Title
Water Pollution Discharges: Economic
Instruments
Nitrate dynamics in relation to lithology
and hydrologic ow path in a river
riparian zone
Submerged Aquatic Vegetation-based
Treatment Wetlands for Removing
Phosphorus from Agricultural Runoff:
Response to Hydraulic and Nutrient
Loading
Geographic Distribution of Endangered
Species in the United States
Economic Analysis as a Basis for
Large-Scale Nitrogen Control Deci-
sions: Reducing Nitrogen Loads to the
Gulf of Mexico.
Great Lakes Commission Point-Coun-
terpoint on USEPA's Trading Policy
HSPFParm:An Interactive Database
for HSPF Model Parameters, Version
1.0
AAA Author
Department for
Environment, Food &
Rural Affairs
Devito, K.J., D.
Fitzgerald, A.R. Hill,
and R. Aravena
Dierberg, F.E., T.A.
DeBusk, S.D. Jack-
son, M.J. Chimney,
and K. Pietro
Dobson, A. P., J.P
Rodrigues, WM.
Roberts, and D.S.
Wlcove
Doering O C M
Ribaudo, F. Diaz-Her-
melo, R. Heimlich, F.
Hitzhusen, C. How-
ard, R. Kazmierczak,
J. Lee, L. Libby, W
Milon M Peters and
A Prato
Donahue, Michael
J.(Ph.D.)
Donigian, A.S., Jr.,
J.C. Imhoff, and J.L.
Kittle, Jr.
Pub.
Date
Jan-98
Jul-Aug-
00
Mar-02
1997
Oct-01
Mar-Apr
2003
1999
Type
Report
Paper
Publisher
Department for Environ-
ment, Food & Rural
Affairs
Journal of environmental
quality. July/Aug 2000. v.
29 (4) p. 1 075-1 084.
Water Resources. 2005
Mar;36(6): 1409-22.
Science, 275: 550-555
ScientificWorldJournal.
2001 Oct 23;1 Suppl
2:968-75. PMID:
1 2805894 [PubMed- in-
dexed for MEDLINE]
Advisor, Great Lakes
Trading Network, March/
April 2003Volume 16,
No.2
EPA-823-R-99-004. U.S.
EPA, Washington DC
38pp.
Comments
http://www.defra.gov.uk/environment/water/quality/econinst1 /in-
dex, htm
Note: Annex 3 International experience (http://www.defra.gov.
uk/environment/water/quality/econinst1/eiwp09.htm)
Economic analysis can be a guide to determining the level of
actions taken to reduce nitrogen (N) losses and reduce envi-
ronmental risk in a cost-effective manner while also allowing
consideration of relative costs of controls to various groups.
The biophysical science of N control, especially from nonpoint
sources such as agriculture, is not certain. Wdespread precise
data do not exist for a river basin (or often even for a water-
shed) that couples management practices and other actions to
reduce nonpoint N losses with specific delivery from the basin.
The causal relationships are clouded by other factors in uenc-
ing N ows, such as weather, temperature, and soil charac-
teristics. Even when the science is certain, economic analysis
has its own sets of uncertainties and simplifying economic
assumptions. The economic analysis of the National Hypoxia
Assessment provides an example of economic analysis based
on less than complete scientific information that can still provide
guidance to policy makers about the economic consequences
of alternative approaches. One critical value to policy makers
comes from bounding the economic magnitude of the conse-
quences of alternative actions. Another value is the identification
of impacts outside the sphere of initial concerns. Such analysis
can successfully assess relative impacts of different degrees of
control of N losses within the basin as well as outside the basin.
It can demonstrate the extent to which costs of control of any
one action increase with the intensity of application of control.
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#
161
162
163
164
165
166
167
168
Title
Modelling Nitrogen Transformations in
Freshwater Wetlands: Estimating Nitro-
gen Retention and Removal in Natural
Wetlands in Relation to their Hydrology
and Nutrient Loadings
Pollution Diffuse et Gestion du Milieu
Agricole: Transferts Compares de
Phosphore et d'Azote dans un Petit
Bassin Versant Agricole: Non-Point
Pollution and Management of Agricul-
tural Areas: Phosphorus and Nitrogen
Transfer in an Agricultural Watershed
Phosphorus saturation potential: a
parameter for estimating the longevity
of constructed wetland systems
Evaluation of Total Nitrogen Pollution
Reduction Strategies in a River Basin:
A Case Study
Phosphorus retention and sorption by
constructed wetland soils in southeast
Ireland
The Three Rivers Project-Water
Quality Monitoring and Management
Systems in the Boyne, Liffey and Suir
Catchments in Ireland
Phosphorus Trade Credits for Non-
Point Source Projects
Design methdology of free water sur-
face constructed wetlands
AAA Author
D0rge, Jesper
Dorioz, J.M. and A.
Ferhi
Drizo, A., Y. Co-
meau, C. Forget, R.P
Chapuis
Drolc, A., J.Z. Kon-
dan, and M. Cotman
Dunne, E.J., N. Culle-
ton, G. O'Donovan, R.
Harrington, K. Daly
Earle, J.R.
Earles, T. Andrew,
Wayne F. Lorenz, and
Wilbur L. Koger
Economopoulou, M.A.
and V.A. Tsihrintzis
Pub.
Date
Sep-94
Feb-94
Nov-02
2001
Nov-05
2003
2005
Dec-04
Type
Paper
Paper
Publisher
Ecological Modelling, Vol-
umes 75-76, September
1 994, Pages 409-420
Water Research, Volume
28, Issue 2, February
1 994, Pages 395-41 0
Environmental Science &
Technology. Nov 1 , 2002.
v. 36 (21 ) p. 4642-4648.
Water Sci Technol.
2001 ; 44(6): 55-62. PMID:
11700664
Water Research. 2005
Nov., v. 39, issue 18, p.
4355-4362.
Water Sci Technol.
2003;47(7-8):217-25.
PMID: 12793683
World Water Congress
2005 Impacts of Global
Climate Change
World Water and Envi-
ronmental Resources
Congress 2005
Raymond Walton - Editor,
May 15-19, 2005, An-
chorage, Alaska, USA
Water Resources Man-
agement. 2004 Dec., v.
18, no. 6, p. 541-565.
Comments
In this paper, the methodology of the material ow analysis
is presented and applied to develop a nitrogen balance in a
river basin and to evaluate different scenarios for total nitrogen
pollution reduction. Application of the methodology is illustrated
by means of a case study on the Krka river, Slovenia. Different
scenarios are considered: the present level of sewerage and
treatment capacities, different stages of wastewater treatment
and management of agricultural activities on land. The results
show that beside ef uents from wastewater treatment plants,
agriculture contributes significantly to the total annual nitrogen
load. Therefore, in order to protect river water quality and drink-
ing water supply, strategies to manage agricultural nitrogen will
be needed in addition to reduction of point sources by means
of wastewater collection and implementation of nutrient removal
technology.
http://scitation.aip. org/getabs/servlet/GetabsServlet?prog=norm
al&id=ASCECP0001 7304079200021 4000001 &idtype=cvips&g
ifs=yes
Available for purchase
http://www.kluweronline.com/issn/0920-4741/contents
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#
169
170
171
172
173
174
175
176
177
178
179
180
181
Title
DUFLOW, a microcomputer pack-
age for simulation of one-dimentional
unsteady ow and water quality in open
channel systems
Effective Enforcement and Compli-
ance in the EU ETS: A View from the
Financial Sector
Performance of Constructed Wetland
System for Public Water Supply
The Impact of a Riparian Wetland on
Streamwater Quality in a Recently Af-
forested Upland Catchment
Nonpoint Source Pollution Control:
Breaking the Regulatory Stalemate
Background Information on Water
Quality Trading and Wetland Mitigation
Banking by the Environmental Law
Institute
Water Quality Trading Nonpoint Credit
Bank Model
Great Lakes Protection Fund - Final
Report
Market-Based Approach to Ecosystem
Improvement
- Grant #609
Fertile Ground: Nutrient Trading's
Potential to Cost-effectively Improve
Water Quality.
2002 Cost for Connecticut Nitrogen
Trades
Stormwater Trading Articles
Using Tradable Credits to Control
Excess Stormwater Runoff
Prevention of Mosquito Production at
an Aquaculture Wastewater Reclama-
tion Plant in San Diego, California
using an innovative sprinkler system
AAA Author
EDS.
Edwards, Rupert
Elias, J.M., E. Salati
Filho, and E. Salati
Emmett, B.A., J.A.
Hudson, PA. Coward
and B. Reynolds
Environmental De-
fense
Environmental Law
Institute
Environmental Trad-
ing Network
Environmental Trad-
ing Network
Environmental Trad-
ing Network
Environmental Trad-
ing Network
EPA National Risk
Management Re-
search Laboratory
EPA National Risk
Management Re-
search Laboratory
Epibare, R., E. Hei-
dig, and D.W Gibson
Pub.
Date
1998
3/16-
18/2004
2001
Nov-94
2003
2000
Ac-
cessed
Jan. 31,
2006
1993
Type
Presentation
Web page
Paper
Paper
Attachment
Articles
Report
Publisher
Leidchendam, The Neth-
erlands.
Climate Change Capital
Water Science Technol-
ogy. 2001 ;44(1 1 -1 2):579-
84.
Journal of Hydrology,
Volume 162, Issues 3-4,
November 1994, Pages
337-353
Environmental Trading
Network
Environmental Law
Institute
National Association of
Conservation Districts
Environmental Trading
Network
World Resources Insti-
tute, Washington, DC.
Environmental Trading
Network
EPA National Risk
Management Research
Laboratory
EPA National Risk
Management Research
Laboratory
In: Bulletin of the Society
for Vector Ecology
18(1):40-44.
Comments
http://www.inece.org/emissions/edwards.pdf
http://www.envtn.org/docs/TradingBankModelPaper.doc
CREDIT SALE REVENUE SCENARIOS: http://www.envtn.
org/docs/TradingBankModel-CreditScenarios.doc
http://www.envtn.org/docs/finalGLPFreport.pdf
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
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#
182
183
184
185
186
187
188
189
190
191
192
193
Title
Concept Paper for a Nutrient Trading
Policy, Revision 5
Ecological Engineering for Wastewater
Treatment
Cypress Swamps
The Potential for Nutrient Trading in
Minnesota: The Case of the Minnesota
River Valley
Market-Based Incentive and Water
Quality
The Use of Water Quality Trading
and Wetland Restoration to Address
Hypoxia in the Gulf of Mexico
Nutrient Runoff Creates Dead Zone
A Climate and Environmental Strategy
for U.S. Agriculture
Stable Isotope Dynamics of Nitrogen
Sewage Ef uent Uptake in a Semi-arid
Wetland
Pollution Trading to Offset New Pol-
lutant Loadings-A Case Study in the
Minnesota River Basin
Preliminary Analysis of Water Qual-
ity Trading Opportunities in the Great
Miami River Watershed, Ohio
Point-Nonpoint Source Water Quality
Trading: A Case Study in the Minnesota
River Basin
AAA Author
Eskin, R. and V.
Kearney
Etnier, C. and B.
Guterstam
Ewel and Odum
Faeth, P.
Faeth, P.
Faeth, Paul World
Resources Institute
Faeth, Paul and G.
Tracy Mehan, III
Faeth, Paul and
Greenhalgh, Suzie
Fair, Jeanne M. and
Jeffrey M. Heikoop
Fang, F. and K.W
Easter
Fang, F, M. S. Kieser,
D. L. Hall, N. C. Ott,
and S. C. Hippensteel
Fang, Feng (Andrew),
K. William Easter, and
Patrick L. Brezonik
Pub.
Date
Aug-97
1991
1985
Feb-98
1999
7/11-
12/2005
Jan-05
Nov-00
Oct-05
Jul-03
un-
known
2005
Type
Paper
Draft Report
Paper
Presentation
Paper
Paper
presentation
Paper
Journal Article
Publisher
Maryland Department of
the Environment
Bokskogen, Gothenburg,
Sweden
University of Florida
Press, Gainesville, FL.
1985.
World Resources Institute
World Resources Institute
PowerPoint Presentation
WRI Features, Vol. 3, No.
1 . World Resources Insti-
tute, Washington, DC.
WRI Issue Brief, World
Resources Institute,
Washington, DC.
Environmental Pollu-
tion, In Press, Corrected
Proof, Available online 4
October 2005
American Agricultural
Economics Associa-
tion Annual Meeting in
Montreal, Canada, July
27-30, 2003
American Society of
Agricultural and Biological
Engineers, St. Joseph,
Michigan www.asabe.org
Journal of the Ameri-
can Water Resources
Association (JAWRA)
41(3):645-658.
Comments
http://www.igc.org/wri/incentives/faeth.html
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
This paper provides a detailed overview of two water pollution
trading projects in Minnesota and tries to answer the question:
have these two projects been cost-effective and environmentally
beneficial? Specific objectives of this paper include: (1) to pro-
vide an in-depth examination of the two point-nonpoint source
trading projects, (2) to conduct cost effectiveness analysis of
the nonpoint source loading reduction practices used in the
two projects for trading, (3) to evaluate the role of scientific un-
certainty played in these two projects, and (4) to look for other
social benefits that such offsetting pollution trading efforts can
offer to a watershed.
http://asae.frymulti.com/abstract.asp?aid=18044&t=2
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#
194
195
196
197
198
199
200
201
202
203
Title
Physical and chemical characteristics
of freshwater wetland soils
Wetlands: the lifeblood of wildlife
Seasonal and Storm Event Nutrient
Removal by a Created Wetland in an
Agricultural Watershed
Wetland nutrient removal: a review of
the evidence
Phosphorus ux from wetland soils af-
fected by long-term nutrient loading
Capped and Non-capped Emissions
Trading: Applying Lessons from Water
Quality Trading
The potential role of ponds as buffer
zones
Balancing Wildlife Needs and Nitrate
Removal in Constructed Wetlands:
The Case of the Irvine Ranch Water
District's San Joaquin Wildlife Sanctu-
ary
Environmental Laws:
Summaries of Statutes Administered
by the Environmental Protection
Agency
Nitrate removal in a riparian wetland
of the Appalachian Valley and ridge
physiographic province
AAA Author
Faulkner, S.P and
C.J. Richardson
Feierabend, J.S.
Fink, Daniel F. and
William J. Mitsch
Fisher, J. and M.C.
Acreman
Fisher, M.M. and K.R.
Reddy
Fisher-Vanden, K.
and H. Jacobs, C.
Schary
Fleischer, S; Joels-
son, A; Stibe, L
Fleming-Singer, Maia
S. and Alexander J.
Home
Fletcher, Susan
(Coordinator
Specialist in Environ-
mental Policy
Resources, Science
and Industry Division)
Flite, O.P III., R.D.
Shannon, R.R.
Schnabel, and R.R.
Parizek
Pub.
Date
1989
1989
Dec-04
Aug-04
Jan-
Feb-01
2002
Nov-05
Mar-05
Jan-
Feb-01
Type
Working paper
Briefing
Publisher
In: Constructed Wetlands
for Wastewater Treatment
- Municipal, Industrial,
and Agricultural. Lewis
Publishers, Chelsea, Ml.
In: D.A. Hammer (ed.)
Constructed Wetlands for
Wastewater Treatment,
Municipal, Industrial and
Agricultural. Lewis Pub-
lishers, Chelsea, Ml.
Ecological Engineering;
23(4-5): 31 3-325. Dec 30,
2004.
Hydrology and earth sys-
tem sciences. 2004 Aug.,
v. 8, no. 4, p. 673-685.
Journal of environmental
quality. Jan/Feb 2001 . v.
30(1) p. 261-271.
Quest Environmental,
PO BOX 45, Harpenden,
Hertfordshire, AL5 5LJ
(UK), pp. 140-146. 1997.
Ecological Engineer-
ing, In Press, Corrected
Proof, Available online 28
November 2005
CRS Report for Congress
Journal of environmental
quality. Jan/Feb 2001 . v.
30(1) p. 254-261.
Comments
http://www.copernicus.org/EGU/hess/publishedjiapers.html
Governmental programmes and international agreements to
counteract eutrophication have largely not attained agreed goals
(e. g. reduction by half of the anthropogenic nitrogen load on
Swedish coastal waters, to be carried out between 1985 and
1995). To attain the agreed goal of a 50 percent reduction of the
nitrogen transport in streams, decreased agricultural leaching
must be combined with extensive pond and wetland construc-
tion.
http://www.ncseonline.org/nle/crsreports/05mar/RL30798.pdf
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#
204
205
206
207
208
209
210
211
212
213
214
215
216
Title
Nitrogen Removal from Domestic
Wastewater Using the Marshland Up-
welling System
Point-Nonpoint Pollutant Trading Study
Basinlink
Watershed-Based Trading & The Law:
Wisconsin's Experience
A Test of Four Plant Species to Reduce
Total Nitrogen and Total Phosphorus
from Soil Leachate in Subsurface Wet-
land Microcosms
Nitrate Removal by Denitrification in Al-
luvial Ground Water: Role of a Former
Channel
Detritus Processing and Mineral Cy-
cling in Seagrass (Zostera) Litter in an
Oregon Salt Marsh
Design and Construction of Demon-
stration/Research Wetlands for Treat-
ment of Dairy Farm Wastewater
The Making of a Regulatory Crisis:
Restructuring New York City's Water
Supply
Ecosystem Structure, Nutrient Dynam-
ics, and Hydrologic Relationships in
Tree Islands of the Southern Ever-
glades, Florida, USA
Telephone Interview with Rich Gan-
non, North Carolina Division of Water
Quality
WQC Item no. 3 EMC Item no. 03-38
Request for Approval of Local Nitrogen
Strategies
Tar-Pamlico Agriculture Rule: A Report
to the NC Environmental Management
Commission from the Tar-Pamlico
Basin Oversight Committee
Nutient Enrichment of Wetland Veg-
etation and Sediments in Subtropical
Pastures
AAA Author
Fontenot, Jeremy,
Dorin Bolder, and
Kelly A. Rusch
Fordiani, R.
Fox-Wolf Basin 2000
Fox-Wolf Basin 2000
Fraser, Lauchlan H.,
Spring M. Carty and
David Steer
Fustec, E., A. Mari-
otti, X. Grille and J.
Sajus
Gallagher, John L.,
Harold V. Kibby and
Katherine W Skirvin
Gamroth, M.J. and
J.A. Moore
Gandy, Matthew
Gann, Tiffany,
G.Childers, Daniel L.
Troxler, and Damon
N. Rondeau
Gannon, Rich
Gannon, Rich
Gathumbi, S.M., PJ.
Bohlen, and D.A.
Graetz
Pub.
Date
Jan-06
Jun-96
2000
2000
Sep-04
Mar-91
Oct-84
Apr-93
Sep-97
Aug-05
09-Dec-
05
October
8-9,
2003
2005
Type
Presentation
Newsletter
Report
Paper
Publisher
Ecological Engineer-
ing, In Press, Corrected
Proof, Available online 6
January 2006
Water Environment Fed-
eration and U.S. EPA
Vol. 2, No.3.
Bioresource Technology;
94(2): 185-192. Sept
2004.
Journal of Hydrology,
Volume 123, Issues 3-4,
March 1991, Pages
337-354
Aquatic Botany, Volume
20, Issues 1 -2, October
1 984, Pages 97-1 08
EPA/600/R-93/105. EPA
Environmental Research
Laboratory, Corvallis, OR
Transactions of the
Institute of British Ge-
ographers, Volume 22,
Issue 3, Page 338-358,
Sep 1997
Forest Ecology and Man-
agement; 21 4(1 -3):1 1 -27.
Aug 2005.
North Carolina Division of
Water Quality
Soil Science Society of
America Journal; 69: 539-
548. 2005.
Comments
Published in Proceedings of Watersheds '96.
http://www.epa.gov/owowwtr1/watershed/Proceed/fordiani.html
http://www.fwb2k.org/research/legalrpt/tradelaw.htm
Report to the N.C. Environmental Management Comission
(EMC) from the the Basin Oversight Committee (BOC) on the
progress of the Nitrogen Reduction Program and to obtain EMC
approval of fourteen local strategies for achieving the Agricul-
ture rule's basinwide nitrogen goal of a 30% reduction in loading
from baseline 1991 levels by 2006.
http://h2o.enr.state.nc.us/nps/EMCRpt-LocStrtgs10-03prn.pdf
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217
218
219
220
221
222
223
224
225
226
227
Title
The use of mangrove wetland as a
biofilter to treat shrimp pond ef uents:
preliminary results of an experiment on
the Caribbean coast of Colombia
The Use of Free Surface Constructed
Wetland as an Alternative Process
Treatment Train to Meet Unrestricted
Water Reclamation Standards
Suitability of a Treatment Wetland for
Dairy Wastewaters
Horizontal Subsurface Flow Systems
in the German Speaking Countries:
Summary of Long-term Scientific and
Practical Experiences; Recommenda-
tions
Nitrogen Transformations in a Wetland
Receiving Lagoon Ef uent: Sequen-
tial Model and Implications for Water
Reuse
Nitrogen Removal in Artificial Wetlands
Role of Aquatic Plants in Wastewater
Treatment by Artificial Wetlands
The Removal of Heavy Metals by Artifi-
cial Wetlands
Mass Loss, Fungal Colonisation and
Nutrient Dynamics of Phragmites aus-
tralis Leaves During Senescence and
Early Aerial Decay
Environmental Flows and Water Quality
Objectives for the River Murray
A Comparison of Rain-related Phos-
phorus and Nitrogen Loading from Ur-
ban, Wetland, and Agricultural Sources
AAA Author
Gautier, D., J. Ama-
dor, and F. Newmark
Gearheart, R.A.
Geary, P.M. and J.A.
Moore
Geller, Gunther
Gerke, Sara, Law-
rence A. Baker, and
Ying Xu
Gersberg, R.M., B.V.
Elkins and C.R. Gold-
man
Gersberg, R.M., B.V.
Elkins, S.R. Lyon and
C.R. Goldman
Gersberg, R.M., S.R.
Lyon, B.Y. Elkins, and
C.R. Goldman
Gessner, Mark O.
Gippel, C., T Jacobs,
and T. McLeod
Glandon, R.P, F.C.
Payne, C.D. McNabb
and T.R. Batterson
Pub.
Date
Oct-01
1999
1999
1997
Nov-01
1983
Mar-86
1984
Apr-01
2002
1981
Type
Paper
Publisher
Aquaculture research.
Oct2001.v. 32 (10) p.
787-799.
Water Science and
Technology, Volume 40,
Issues 4-5, 1999, Pages
375-382
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 179-185
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 157-166
Water Research; 35(1 6):
3857-3866. November
2001.
Water Research, Volume
17, Issue 9, 1983, Pages
1 009-1 01 4
Water Research, Volume
20, Issue 3, March 1986,
Pages 363-368
EPA-600/D-84-258. Robt.
S. Kerr Env. Research
Lab., Ada, OK
Aquatic Botany; 69(2-4):
325-339. April 2001 .
Water Sci Technol.
2002;45(11):251-60. MID:
121 71 360 [PubMed- in-
dexed for MEDLINE]
Water Research, Volume
15, Issue 7, 1981, Pages
881 -887
Comments
This paper considers a plan for managing ows in the River
Murray to provide environmental benefits. Described are four
key aspects of the process being undertaken to determine the
objectives, and design the ow options that will meet those
objectives: establishment of an appropriate technical, advisory
and administrative framework; establishing clear evidence for
regulation impacts; undergoing assessment of environmental
ow needs; and filling knowledge gaps.
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228
229
230
231
232
233
234
235
236
237
238
239
240
241
Title
Ecological Considerations in Wetlands
Treatment of Municipal Wastewaters
Surmounting the Engineering Chal-
lenges of Everglades Restoration
Symbiont Nitrogenase, Alder Growth,
and Soil Nitrate Response to Phospho-
rus Addition in Alder (Alnus incana ssp.
rugosa) Wetlands of the Adirondack
Mountains, New York State, USA
Freshwater Wetlands: Ecological Pro-
cesses and Management Potential
The Origins and Practice of Emissions
Trading
Modelling drainage practice impacts on
the quantity and quality of stream ows
for an agricultural watershed in Ohio
Rule Enforcing Selenium Load Alloca-
tion and Establishing a Tradable Loads
Program for Water Year 1999
The Nutrient Assimilative Capacity of
Maerl as a Substrate in Constructed
Wetland Systems for Waste Treatment
Second Semi-Annual Report to the
Great Lakes Protection Fund
2nd Semi-Annual Report
Categorization of Issues
List of Issues Encountered
Differences in wetland plant commu-
nity establishment with additions of
nitrate-N and invasive species (Phalaris
arundinaceae and Typha xglauca)
Constructed Wetlands for River Recla-
mation: Experimental Design, Start-up
and Preliminary Results
AAA Author
Godfrey, P.J., E.R.
Kaynor, S. Pelczarski
and J. Benforado
(eds)
Goforth, G.F.
Gokkaya, Kemal,
Todd M. Hurd, and
Dudley J. Raynal
Good, R.E., D.F.
Whigham, and R.L.
Simpson (eds)
Gorman, H.S. and
B.D. Solomon
Gowda, PH., A.D.
Ward, D.A. White,
D.B. Baker, and T.J.
Logan
Grassland Basin
Drainage Steering
Committee
Gray, Shalla, John
Kinross, Paul Read,
and Angus Marland
Great Lakes Trading
Network
Great Lakes Trading
Network
Great Lakes Trading
Network
Great Lakes Trading
Network
Green, E.K. and S.M.
Galatowitsch
Green, Michal, Iris
Safray and Moshe
Agami
Pub.
Date
1985
2001
Jan-06
1978
2002
1998
Jan-99
Jun-00
Dec-98
Dec-98
Feb-01
Feb-96
Type
Paper
Draft rule
Report
Report
Publisher
Van Nostrand Reinhold
Co., New York, NY
Water Science Technol-
ogy. 2001 ;44(1 1 -1 2):295-
302.
Environmental and Ex-
perimental Botany; 55(1-
2): 97-1 09. Jan 2006.
Academic Press, New
York, NY
Journal of Policy History,
2002
In: Proceedings of the
Seventh International
Symposia of the ASAE,
Orlando, FL.
Grassland Basin Drain-
age Steering Committee
Water Research: 34(8):
2183-2190. June 2000.
Great Lakes Trading
Network
Great Lakes Trading
Network
Great Lakes Trading
Network
Great Lakes Trading
Network
Canadian journal of bota-
ny = Journal canadien de
botanique Feb 2001 . v. 79
(2) p. 170-178.
Bioresource Technol-
ogy, Volume 55, Issue 2,
February 1996, Pages
157-162
Comments
http://www.deq.state.mi.us/swq/trading/htm/GLTNrept2.htm
Includes a summary of trading programs in the Appendices
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242
243
244
245
246
247
248
249
250
251
Title
Standard Methods for the Examination
of Water and Wastewater
A Potential Integrated Water Quality
Strategy for the Mississippi River Basin
and the Gulf of Mexico
Awakening the Dead Zone: An Invest-
ment for Agriculture, Water Quality, and
Climate Change
Suitability of Macrophytes for Nutri-
ent Removal from Surface Flow
Constructed Wetlands Receiving
Secondary Treated Sewage Ef uent in
Queensland, Australia
The Role of Constructed Wetlands
in Secondary Ef uent Treatment and
Water Reuse in Subtropical and Arid
Australia
Nutrient Content of Wetland Plants in
Constructed Wetlands Receiving Mu-
nicipal Ef uent in Tropical Australia
Constructed Wetlands in Queensland:
Performance Efficiency and Nutrient
Bioaccumulation
Indigenous Sediment Microbial Activ-
ity in Response to Nutrient Enrich-
ment and Plant Growth Following a
Controlled Oil Spill on a Freshwater
Wetland
Wetland Functions and Values: The
State of Our Understanding
Cost-effective Nutrient Reductions to
Coupled Heterogeneous Marine Water
Basins: An Application to the Baltic Sea
AAA Author
Greenberg, A.E., L.S.
Clescer, and A.D.
Eaton, eds.
Greenhalgh S, and P.
Faeth
Greenhalgh, Suzie
and Amanda Sauer
Greenway, M.
Greenway, Margaret
Greenway, Margaret
Greenway, Margaret
and Anne Woolley
Greer, C.W, N.
Fortin, R. Roy, L.G.
Whyte, and K. Lee
Greeson, P.E., J.R.
Clark and J.E. Clark
(eds)
Gren, I-M, and
F. Wulff
Pub.
Date
1992
Nov-01
Feb-03
Dec-05
1997
1999
Apr-03
1979
Dec-04
Type
paper
Paper
Paper
Publisher
18th ed. American Public
Health Association. Water
Environment Federation.
Scientific World Journal;
1 (2):976-83. Nov 22,
2001.
WRI Issue Brief, World
Resources Institute,
Washington, DC.
Water Sci Technol.
2003;48(2):121-8.
Ecological Engineering;
25(5): 501 -509. Dec. 1,
2005.
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 135-142
Ecological Engineering,
Volume 12, Issues 1-2,
January 1999, Pages
39-55
Bioremediation Journal;
7(1): 69-80. Apr 15, 2003.
Amer. Water Resources
Assoc., Minneapolis, MN
Regional Environmental
Change, ISSN: 1436-
3798 (Paper) 1436-378X
(Online), Issue: Volume
4, Number 4, pg 159-168
Comments
http://www.ncbi. nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db
=PubMed&list_uids=1 2805841 &dopt=Citation
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
In this paper, the role of nutrient transports between marine ba-
sins is investigated for cost-effective solutions to predetermined
marine basin targets. The interdependent advective nutrient
transports as well as retentions among the seven major marine
basins of the Baltic Sea are described by input-output analysis.
This is in contrast to prior economic studies of transbound-
ary water pollution that include only direct transport between
the basins. The analytical results show that the difference in
impacts between transport specifications depends mainly on
the openness of the basins, that is, their transports with other
basins. The application on Baltic Sea shows significant differ-
ences in costs and policy design between the nutrient transport
specifications. The reason is that the Sea is characterized by
long water and nutrient residence times, so relatively large parts
of nutrients are transported among basins.
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252
253
254
255
256
257
258
259
260
261
262
263
264
Title
The Advantages of a Constructed
Reed Bed Based Strategy for Small
Sewage Treatment Works
Advanced Nitrogen Removal by Rotat-
ing Biological Contactors, Recycle and
Constructed Wetlands
Hydraulic characteristics of a sub-
surface ow constructed wetland for
winery ef uent treatment
Nutrient Removal Processes in Fresh-
water Submersed Macrophyte Systems
High nitrogen : phosphorus ratios
reduce nutrient retention and second-
year growth of wetland sedges
Variation in Nitrogen and Phosphorus
Concentrations of Wetland Plants
Techniques of Water-resources Investi-
gations of the United States Geological
Survey: Laboratory Theory and Meth-
ods for Sediment Analysis
Bank Review and Certification Require-
ments: A Third Party Auditor Perspec-
tive
Nitrogen mineralization in marsh mead-
ows in relation to soil organic matter
content and watertable level
Carbon Source Utilization Profiles as
a Method to Identify Sources of Faecal
Pollution in Water
Where Did All the Markets Go? An
Analysis of EPA's Emissions Trading
Program
Marketable Permits: Lessons for
Theory and Practice
Tar-Pamlico River Basin Program in
North Carolina
AAA Author
Griffin, P. and C.
Pamplin
Griffin, P., P. Jennings
and E. Bowman
Grismer, M.E., M.
Tausendschoen, and
H.L. Shepherd
Gumbricht, Thomas
Gusewell, S.
Gusewell, Sabine and
Willem Koerselman
Guy, H.P.
Habicht, Hank
Global Environment &
Technology Founda-
tion
Hacin, J., J. Cop, and
I. Mahne
Hagedorn, C., J.B.
Crozier, K.A. Mentz,
A.M. Booth, A.K.
Graves, N.J. Nelson,
and R.B. Reneau, Jr.
Hahn, R.W and G.L.
Hester
Hahn, R.W. and G.L.
Hester
Hall and Howett
Pub.
Date
1998
1999
Jul-Aug-
01
Mar-93
May-05
2002
May-05
Jul-11-
12-05
Oct-01
May-03
1989a
1989b
1994
Type
Presentation
Paper
Journal Article
Article
Paper
Publisher
Water Science and Tech-
nology, Volume 38, Issue
3, 1998, Pages 143-150
Water Science and
Technology, Volume 40,
Issues 4-5, 1999, Pages
383-390
Water Environment Fed-
eration. July/Aug 2001 . v.
73 (4) p. 466-477.
Ecological Engineering,
Volume 2, Issue 1 , March
1 993, Pages 1 -30
New Phytologist. 2005
May, v. 166, no. 2, p.
537-550.
Perspectives in Plant
Ecology, Evolution and
Systematics; 5(1): 37-61.
2002.
U. S. Government Print-
ing Office. Washington,
DC
PowerPoint Presentation
Journal of Plant Nutri-
tion and Soil Science =
Zeitschrift fur P anzen-
ernahrung und Boden-
kunde. Oct 2001. v. 164
(5) p. 503-509.
Journal of Applied
Microbiology, Volume 94,
Issue 5, Page 792-799,
May 2003
Yale Journal on Regula-
tion, 6, 109-153
Ecology Law Quarterly,
16, 361-406.
Comments
http://www3.interscience.wiley.com/cgi-bin/jtoc?ID=1 0008342
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#
265
266
267
268
269
270
271
272
273
274
275
276
Title
Guide to Establishing a Point/Nonpoint
Source Reduction Trading System for
Basinwide Water Quality Management:
The Tar-Pamlico River Basin Experi-
ence.
Background: The History and Status of
Wetland Mitigation Banking and Water
Quality Trading
Background: The History and Status of
Wetland Mitigation Banking and Water
Quality Trading
Control of Denitrification in a Septage-
treating Artificial Wetland: The Dual
Role of Particulate Organic Carbon
Nitrogen Balance and Cycling in an
Ecologically Engineered Septage Treat-
ment System
Creating Freshwater Wetlands
Constructed Wetlands for Wastewater
Treatment - Municipal, Industrial &
Agricultural
Design Principles for Wetland Treat-
ment Systems
The Potential For Water Quality Trad-
ing To Help Implement The Cheat
Watershed Acid Mine Drainage Total
Maximum Daily Load In West Virginia
Exploring Trading to Reduce Impacts
from Acid Mine Drainage
Methylmercury formation in a wetland
mesocosm amended with sulfate
Treatment at Different Depths and
Vertical Mixing Within a 1-m Deep Hori-
zontal Subsurface- ow Wetland
AAA Author
Hall, J. and C.
Howett, Kilpatrick &
Cody
Hall, Lynda U.S. EPA
Hall, Lynda U.S. EPA
Hamersley, M. Robert
and Brian L. Howes
Hamersley, M. Rob-
ert, Brian L. Howes,
David S. White,
Susan Johnke, Dale
Young, Susan B.
Peterson, and John
M.Teal
Hammer, D.A.
Hammer, D.A. (ed)
Hammer, D.E. and
R.H. Kadlec
Hansen, E., M. Christ,
J. Fletcher, J.T. Petty,
P. Ziemkiewicz, and
R.S. Herd
Hansen, Evan
Harmon, S.M.,
J.K.King, J.B. Glad-
den, G.T. Chandler,
and L.A. Newman
Headley, Thomas R.,
Eamon Herity, and
Leigh Davison
Pub.
Date
Jul-95
7/11-
12/2005
7/11-
12/2005
Oct-02
Oct-01
1992
1989
1983
Apr-04
Jul-03
Jan-04
Dec-05
Type
Paper
Presentation
Presentation
Report
PowerPoint
Publisher
North Carolina Depart-
ment of Health and
Natural Resources,
Division of Environmen-
tal Management, Water
Quality Section
EPA-904-95-900.
Audio Recording
PowerPoint Presentation
Water Research; 36(1 7):
4415-4427. Oct 2002.
Ecological Engineering;
18(1): 61 -75. October
2001.
Lewis Publishers, Inc.
Boca Raton, FL.
Lewis Publ., Chelsea, Ml
EPA- 600/S2-83-026. EPA
Municipal Environmental
Research Lab, Cincin-
nati, OH
Friends of the Cheat
http://www.cheat.org/
Environmental Science &
Technology. 2004 Jan. 15,
v. 38, no. 2, p. 650-656.
Ecological Engineering;
25(5): 567-582. Dec.
2005.
Comments
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqt_main.htm
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqtjnain.htm
http://downstreamstrategies.com/CheatReport.zip
2003 National Forum on Water Quality Trading
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277
278
279
280
281
282
283
284
285
Title
The Role of Marsh Plants in the
Transport of Nutrients as Shown by a
Quantitative Model for the Freshwater
Section of the Elbe Estuary
Agricultural Resources and Environ-
mental Indicators, 2003, Agriculture
Handbook No. (AH722)
Fate of Physical, Chemical, and
Microbial Contaminants in Domestic
Wastewater Following Treatment by
Small Constructed Wetlands
Treatment of Primary-Settled Urban
Sewage in Pilot-Scale Vertical Flow
Wetland Filters: Comparison of Four
Emergent Macrophyte Species Over a
12 Month Period
Nutrient Farming and Traditional Re-
moval: An Economic Comparison
Nitrogen Farming: Using Wetlands to
Remove Nitrogen From Our Nation's
Waters
Stimulating Creation of a Point/Non-
Point Source Trading System on a
Watershed Scale
Nitrogen Farming: Harvesting a Differ-
ent Crop
Water Quality Improvement by Four
Experimental Wetlands
AAA Author
Heckman, Charles W
Heimlich, Ralph
Hench, Keith R., Gary
K. Bissonnette, Alan
J. Sexstone, Jerry
G. Coleman, Keith
Garbutt, and Jeffrey
G. Skousen
Heritage, Alan, Pino
Pistillo, K. P. Sharma
and I. R. Lantzke
Hey, D., J. Kostel, A.
Hurter, R. Kadlec
Hey, Donald The
Wetlands Initiative
Hey, Donald The
Wetlands Initiative
Hey, Donald L. (Ph.
D.)
Hey, Donald L., Ann
L. Kenimer and Kirk
R. Barrett
Pub.
Date
1986
Feb-03
Feb-03
1995
2005
May-02
7/11-
12/2005
Mar-02
Dec-94
Type
Report
Report
Presentation
Publisher
Aquatic Botany, Volume
25, 1986, Pages 139-151
Economic Research
Service, U.S. Department
of Agriculture. February,
2003.
The Science of The Total
Environment, Volume
301, Issues 1-3, 1 Janu-
ary 2003, Pages 13-21
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 295-304
Water Environmental
Research Foundation
doc#03-WSO-6CO
The Wetlands Initiative,
Chicago, IL.
Audio Recording
Restoration Ecology: The
Journal of the Society for
Ecological Restoration,
Vol. 10, No. 1, March
2002
Ecological Engineer-
ing, Volume 3, Issue 4,
December 1994, Pages
381 -397
Comments
This report identifies trends in land, water, and biological
resources and commercial input use, reports on the condi-
tion of natural resources used in the agricultural sector, and
describes and assesses public policies that affect conserva-
tion and environmental quality in agriculture. Combining data
and information, this report examines the complex connections
among farming practices, conservation, and the environment,
which are increasingly important components in U.S. agriculture
and farm policy.
http://www.ers.usda.gov/publications/arei/ah722/dbgen.htm
http://www.wetlands-initiative.org/images/03WSM6COweb.pdf
Summary Report of Four Workshops. Background information
for the National Forum on Synergies Between Water Quality
Trading and Wetland Mitigation Banking - http://www2.eli.org/re-
search/wqtjnain.htm
Introduces the concept of "nutrient farming" , which would create
wetlands for their water quality improvement function in order to
create nutrient trading credits. The paper describes a potential
market for credits due to wetland losses and nitrogen fertilizer
use in the Mississippi River Basin. A cost comparison between
waste water plants and potential "nutrient farms" is provided.
http://www. wetlands-initiative. org/images/pdfs_pubs/vol4n01 .pdf
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286
287
288
289
290
291
292
293
294
Title
Nutrient Farming: The Business of
Environmental Management
Nutrient Farming: The Business of
Environmental Management - Execu-
tive Summary
Removal Efficiency of Three Cold-cli-
mate Constructed Wetlands Treating
Domestic Wastewater: Effects of Tem-
perature, Seasons, Loading Rates and
Input Concentrations
The use of microbial tracers to monitor
seasonal variations in ef uent retention
in a constructed wetland
Nitrogen removal from waste treatment
pond or activated sludge plant ef uents
with free-surface wetlands
The Ecology and Management of Wet-
lands (2 vols.)
Differences in Social and Public Risk
Perceptions and Con icting Impacts on
Point/Nonpoint Trading Ratios
Policy Objectives and Economic
Incentives for Controlling Agricultural
Sources of Nnonpoint Pollution
Point-nonpoint Nutrient Trading in the
Susquehanna River Basin
AAA Author
Hey, Donald L, Laura
S. Urban, and Jill A.
Kostel
Hey, Donald L., Laura
S. Urban, and Jill A.
Kostel
Hlum, Trond M. and
Per Stlnacke
Hodgson, C.J., J.
Perkins, and J.C.
Labadz
Home, Alexander J.
Hook, D.D. et. al.
Horan, R.D.
Horan, R.D. and M.O.
Ribaudo
Horan, R.D., J.S.
Shortle, and D.G.
Abler
Pub.
Date
Apr-05
Apr-05
1999
Nov-04
1995
1988
Nov-01
1999
2002
Type
Paper
Summary
Paper
Journal Article
Publisher
Ecological Engineering:
The Journal of Ecosys-
tem Restoration, Vol. 24,
No. 4 (April 5, 2005), pp
279-287.
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 273-281
Water Research. 2004
Nov., v. 38, issue 18, p.
3833-3844.
Water Science and Tech-
nology, Volume 31 , Issue
12, 1995, Pages 341 -351
Croom Held, Ltd.,
London/Timber Press,
Portland, OR
American Journal of Agri-
cultural Economics; 83(4):
934. Nov 2001 .
Journal of the American
Water Resources Asso-
ciation, 35(5), 1023-1035.
Water Resources Re-
search, 38(5), 1-13.
Comments
Available online at www.sciencedirect.com.
http://www. wetlands-initiative. org/images/pdfs_pubs/EcoEng-
Proof.pdf
http://www. wetlands-initiative. org/images/pdfs_pubs/nfarm. busi-
ness-envimgmt.pdf
http://www. wetlands-initiative. org/images/pdfs_pubs/harvesting.
diff.crop.pdf
Most research on point-nonpoint trading focuses on the choice
of trading ratio (the rate point source controls trade for nonpoint
controls), although the first-best ratio is jointly determined with
the optimal number of permits. In practice, program managers
often do not have control over the number of permits — only
the trading ratio. The trading ratio in this case can only be
second-best. We derive the second-best trading ratio and,
using a numerical example of trading in the Susquehanna
River Basin, we find the values are in line with current ratios,
but for different reasons than those that are normally provided.
http://www.blackwell-synergy.eom/links/doi/10.1 1 1 1/0002-
9092.00220?cookieSet=1
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#
295
296
297
298
299
300
301
302
303
304
Title
Differences in Social and Public Risk
Perceptions and Con icting Impacts on
Point/Nonpoint Trading Ratios
When Two Wrongs Make a Right: Sec-
ond-Best Point/Nonpoint Trading Ratios
Field Examination on Reed Growth,
Harvest and Regeneration for Nutrient
Removal
Background: The History and Status of
Wetland Mitigation Banking and Water
Quality Trading
Water Quality Study Feedstuffs
Nitrogen Removal in Constructed
Wetlands Employed to Treat Domestic
Wastewater
Effect of design parameters in hori-
zontal ow constructed wetland on the
behaviour of volatile fatty acids and
volatile alkylsulfides
Assessment of Environmental and
Economic Benefits Associated with
Streambank Stabilization
and Phosphorus Retention
Use of oating vegetation to remove
nutrients from swine lagoon wastewater
Nitrogen and Phosphorus Removal
from Plant Nursery Runoff in Vegetated
and Unvegetated Subsurface Flow
Wetlands
AAA Author
Horan, Richard D.
Horan, Richard D.
and James S. Shortle
Hosoi,Y.,Y. Kido, M.
Miki and M. Sumida
Hough, Palmer U.S.
EPA
Howie, Michael
Huang, J., R.B.
Reneau, Jr., and C.
Hagedorn
Huang, Y, L. Ortiz,
P. Aguirre, J. Garcia,
R. Mujeriego, J.M.
Bayona
Hubbard, Lisa C.,
David S. Biedenharn,
and Steven L. Ashby
Hubbard, R.K., G.J.
Gascho, G.L. Newton
Huett, D.O., S.G.
Morris, G. Smith, and
N. Hunt
Pub.
Date
Nov-01
May-05
1998
7/11-
12/2005
Jun-04
Jun-00
May-05
May-03
Nov-
Dec-04
Sept-05
Type
Paper
Presentation
Publisher
American Journal of Agri-
cultural Economics
Volume 83 Issue 4 Page
934 - November 2001
doi:10.1 11 1/0002-
9092.00220
American Journal of
Agricultural Economics,
Volume 87 Issue 2 Page
340 -
Water Science and Tech-
nology, Volume 38, Issue
1 , 1 998, Pages 351 -359
Audio Recording
Water Research; 34(9):
2582-2588. June 15,
2000.
Chemosphere. 2005 May,
v. 59, issue 6, p. 769-777.
ERDCWQTN-AM-14
Transactions of the
ASAE. 2004 Nov-Dec, v.
47, no. 6, p. 1963-1972.
Water Resources, 39(14):
3259-72. Sept 2005.
Comments
If stochastic nonpoint pollution loads create socially costly risk,
then an economically optimal point/nonpoint trading ratio the
rate point source controls trade for nonpoint controls is adjusted
downward (a risk reward for nonpoint controls), encouraging
more nonpoint controls. However, in actual trading programs,
ratios are adjusted upward in response to nonpoint uncertain-
ties (a risk premium for nonpoint controls). This contradiction
is explained using a public choice model in which regulators
focus on encouraging abatement instead of reducing damages.
The result is a divergence of public and social risk perceptions,
and a trading market that encourages economically suboptimal
nonpoint controls.
http://www.blackwell-synergy.com/links/doi/10.11 1 1/J.1467-
8276.2005.00726.x
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqt_main.htm
http://www.findarticles.com/p/articles/mi_go1470/is 200406/
ai_n6534686
Techincal notes provide the results of a creek enhancement
project in Mass. A summary of bank stabilization treatments
and the conditions of the banks at Year 9 are provided. Erosion
estimates are made using aerial photo interpretation. Total
P and biologically available P are sampled in the bed, bank,
and top of bank. Cost of bank stabilization and cost for total P
removal are estimated, http://el.erdc.usace.army.mil/elpubs/pdf/
wqtnam14.pdf
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305
306
307
308
309
310
311
312
313
314
315
Title
Constructed Treatment Wetland System
Description and Performance
Denitrification potential and carbon
quality of four aquatic plants in wetland
microcosms
State of the Art for Animal Wastewater
Treatment in Constructed Wetlands
Denitrification in a coastal plain riparian
zone contiguous to a heavily loaded
swine wastewater spray field
Designing Stormwater Wetlands for
Small Watersheds
Nitrogen, phosphorus, and organic
carbon removal in simulated wetland
treatment systems
Perchlorate is Not a Common Contami-
nant of Fertilizers
Nitrogen sources in Adirondack
wetlands dominated by nitrogen-fixing
shrubs.
Modeling of nitrogen sequestration in
coastal marsh soils.
Open-air Treatment of Wastewater from
Land-Based Marine Fish Farms in Ex-
tensive and Intensive Systems: Current
Technology and Future Perspectives
Methane Emission Rates from an Om-
brotrophic Mire Show Marked Season-
ality which is Independent of Nitrogen
Supply and Soil Temperature
AAA Author
Humboldt University
Hume, N.P, M.S.
Fleming, and A.J.
Home
Hunt, PG. and M.E.
Poach
Hunt, P.G., T.A. Ma-
theny, and K.C. Stone
Hunt, William F. and
Barbara A. Doll
Hunter, R.G., D.L.
Combs, D.B. George
Hunter, W J.
Hurd, T.M., K. Gok-
kaya, B.D. Kiernan,
D.J. Raynal
Hussein, A.H. and
M.C. Rabenhorst
Hussenot, Jerome,
Sebastien Lefebvre
and Nicolas Brossard
Hutchin, PR., M.C.
Press, J.A. Lee and
T.W. Ashenden
Pub.
Date
2000
Sep-
Oct-02
2001
Nov-
Dec-04
Apr-00
Oct-01
Nov-01
Mar-05
Jan-
Feb-02
Jul-Aug-
98
Sep-96
Type
Paper
Publisher
Humboldt University
Soil Science Society of
America journal. Sept/Oct
2002. v. 66 (5) p. 1 706-
1712.
Water Science Technolo-
gy. 2001 ;44(1 1-1 2): 19-25.
Journal of environmental
quality. 2004 Nov-Dec, v.
33, no. 6, p. 2367-2374.
North Carolina Coop-
erative Extension, North
Carolina State University
Archives of environmen-
tal contamination and
toxicology. Oct 2001 . v. 41
(3) p. 274-281 .
Journal of Agronomy and
Crop Science, Volume
187, Issue 3, Page 203-
206, Nov 2001
Wetlands : the journal
of the Society of the
Wetland Scientists. 2005
Mar., v. 25, no. 1, p. 192-
199.
Soil Science Society of
America journal. Jan/Feb
2002. v. 66 (1 ) p. 324-330.
Aquatic Living Resourc-
es, Volume 1 1 , Issue 4,
July-August 1998, Pages
297-304
Atmospheric Environ-
ment, Volume 30, Issue
17, September 1996,
Pages 301 1-301 5
Comments
http://firehole.humboldt.edu/wetland/twdb.html (January 2006).
http://www.neuse.ncsu.edu/SWwetlands.pdf
The present study developed methods for improving the HPLC
analysis of perchlorate and used these methods to survey 15
US fertilizers for perchlorate. The study found no perchlorate in
any of the fertilizers investigated.
This paper reports methane uxes measured in an area of om-
brotrophic mire at the Migneint in North Wales when nitrogen,
in the form of ammonium and/or nitrate, was applied to plots on
the mire surface. These applications of nitrogen had no effect
on the methane emission rates at any date, with the exception
of the measurement from November 1994. No correlation was
found between methane ux and either soil temperature or
water table.
http://www.sciencedirect.com/science? ob=ArticleURL&
udi=B6VH3-3Y45YRC-R&_coverDate=09%2F30%2F1996&
_alid=375242647&_rdoc=1 &_fmt=&_orig=search&_qd=1 &_
cdi=6055&_sort=d&view=c&_acct=C000050221 &_version=1 &_
urlVersion=0& userid=1 0&md5=0ada691 875c6f090e70e1 8e5b
ae684fe
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316
317
318
319
320
321
322
323
324
325
326
327
Title
Technology Assessment of Wetlands
for Municipal Wastewater Treatment
Proceedings of Wetlands Downunder,
An International Specialist Conference
on Wetlands Systems in Water Pollu-
tion Control
Characterization of microbial communi-
ties and composition in constructed
dairy wetland wastewater ef uent
1st Annual Status Report: Lower Boise
River Ef uent Trading Demonstration
Project
2nd Annual Status Report: Lower Boise
River Ef uent Trading Demonstration
Project
Surface Water: Lower Boise River Sub-
basin Assessment and Total Maximum
Daily Loads
Surface Water: TMDL Implementation
Plans
Surface Water: Snake River - Hells
Canyon Subbasin Assessment and
Total Maximum Daily Loads
Best Management Practice (BMP) List
for the Lower Boise River Pollution
Trading Program
Pretreatment Market System Develop-
ment
Market-Based Trading of Categorical
Pretreatment Limits
Market-Based Approaches to Reduce
Water Pollution: A Pre-Feasibility Study
AAA Author
Hyde, H.C., R.S.
Ross and F.C. Dem-
gen
IAWQ/AWWA
Ibekwe, A.M., C.M.
Grieve, S.R. Lyon
Idaho Department of
Environmental Quality
Idaho Department of
Environmental Quality
Idaho Department of
Environmental Quality
Idaho Department of
Environmental Quality
Idaho Department of
Environmental Quality
Idaho Soil Conserva-
tion Commission
Illinois Environmental
Protection Agency
Illinois Environmental
Protection Agency
Illinois Environmental
Protection Agency,
Bureau of Water and
Environmental Policy
Office
Pub.
Date
1984
1992
Sep-03
May-01
Jun-02
Ac-
cessed
Ac-
cessed
Ac-
cessed
May-02
Undated
Aug-96
Nov-95
Type
Report
Report
Web-site
Web-site
Web-site
BMP List
Paper
Discussion
Paper
Paper
Report
Publisher
EPA 600/2-84-1 54. EPA
Municipal Environmental
Research Lab., Cincin-
nati, OH
Int'l. Assoc. of Water
Quality/Australian Water
& Wastewater Assoc.,
Univ. of New South
Wales, Sydney, Australia
Applied and Environ-
mental Microbiology.
2003 Sept., v. 69, no.9, p.
5060-5069.
Idaho Department of
Environmental Quality
Idaho Department of
Environmental Quality
Idaho Department of
Environmental Quality
Idaho Department of
Environmental Quality
Idaho Department of
Environmental Quality
Idaho Soil Conservation
Commission
Illinois Environmental
Protection Agency
Illinois Environmental
Protection Agency
Illinois Environmental
Protection Agency,
Bureau of Water and En-
vironmental Policy Office
Comments
http://www.deq. state, id. us/water/data_reports/surface_water/tm-
dls/boise_river_lower/boise_river_lower.cfm
http://www.deq. state, id. us/water/data_reports/surface_water/tm-
dls/implementation_plans.cfm
http://www.deq. state, id. us/water/data_reports/surface_water/tm-
dls/snake_river_hells_canyon/snake_river_hells_canyon.cfm
Selected nonpoint source BMPs used to offset a point source's
discharge in the Lower Boise River are described in this paper.
The procedure for generating credits, as well as other trading
program requirements, are described as well. Evaluation and
measurment requirements for BMP monitoring are discussed.
This document will be updated periodically and new BMPs
added to the list of those currently eligible for trading.
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#
328
329
330
331
332
333
334
335
336
337
338
339
Title
Discussion Paper: Conference on Com-
pliance and Enforcement for Emissions
Trading Schemes
Periphyton tissue chemistry and nitro-
genase activity in a nutrient impacted
Everglades ecosystem
Hydrochemistry and Hydrology of For-
est Riparian Wetlands
The Tar-Pamlico River Basin Nutrient
Trading Program
The Tar-Pamlico River Basin Nutrient
Trading Program
Phosphorus adsorption characteristics
of a constructed wetland soil receiving
dairy farm wastewater
Design and Performance of Experimen-
tal Constructed Wetlands Treating Coke
Plant Ef uents
Lessons Learned from the Neuse River
Basin Education Program
The Potential of Natural Ecosystem
Self-purifying Measures for Controlling
Nutrient Inputs
Evaluation of vegetation management
strategies for controlling mosquitoes
in a southern California constructed
wetland
Removal of N, P, BODS, and coliform
in pilot-scale constructed wetland
systems
Microcosm Wetlands for Wastewater
Treatment with Different Hydraulic
Loading Rates and Macrophytes
AAA Author
INECE-Environment
Agency (England and
Wales), Worcester
College, Oxford,
England
Inglett, P.W., K.R.
Reddy, and PV. Mc-
Cormick
Jacks, G. and A.C.
Norrstrbm
Jacobcon, E.M., et al.
Jacobson, E.M., L.E.
Danielson, and D.L.
Hoag
Jamieson, T.S., R.
Gordon, A. Madani
Jardinier, N., G.
Blake, A. Mauchamp,
and G. Merlin
Jennings, Greg,
PhD. and Deanna
Osmond, PhD. (NC
State University)
Jenssen, Petter D.,
Trond Mashlum,
Roger Roseth, Bent
Braskerud, Nina
Syversen, Arnor Nj0s
and Tore Krogstad
Jiannino, J.A. and
W.E.Walton
Jin, G., T Kelley, M.
Freeman, M. Cal-
lahan
Jin, S.R.,Y.F. Lin.T.W
Wang, and D.Y. Lee
Pub.
Date
3/16-
18/2004
2004
Jul-04
Apr-94
1994
Feb-02
2001
Sep-05
1994
Mar-04
2002
2002
Type
Presentation
Paper
Presentation
Publisher
INECE-Environment
Agency (England and
Wales), Worcester Col-
lege, Oxford, England
Biogeochemsitry 67:213-
233
Forest Ecology and
Management; 196(2-3):
187-197. Jul 26, 2004.
Applied Resource
Economics and Policy,
Department of Agricultur-
al & Resource Econom-
ics, North Carolina State
University.
Applied Resource
Economics and Policy
Group, Department of
Agricultural and Resource
Economics
Canadian Journal of Soil
Science. Feb 2002. v. 82
(1) p. 97-104.
Water Science Technol-
ogy. 2001 ;44(1 1-12):
485-91 .
13th National Nonpoint
Source
Monitoring Workshop
Marine Pollution Bulletin,
Volume 29, Issues 6-1 2,
1 994, Pages 420-425
Journal of the American
Mosquito Control Asso-
ciation. 2004 Mar., v. 20,
no. 1, p. 18-26.
International Journal of
Phytoremediation. 2002.
v. 4 (2) p. 127-141.
Journal of Environmental
Quality. 2002 Mar-
Apr;31(2):690-6.
Comments
http://www.bae.ncsu.edu/program/extension/arep/tarpam.html
http://www.bae. ncsu.edu/programs/extension/wqg/nmp_conf/
presentations.html
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#
340
341
342
343
344
345
346
Title
Nutrient Removal from Polluted River
Water by Using Constructed Wetlands
Methane emissions from a constructed
wetland treating wastewater-seasonal
and spatial distribution and depen-
dence on edaphic factors
Metamodelling Phosphorus Best Man-
agement Practices for Policy Use: A
Frontier Approach
Watershed Nutrient Trading Under
Asymmetric Information
Reducing Hypoxia in Long Island
Sound: The Connecticut Nitrogen
Exchange
Sediment and nutrient retention by
freshwater wetlands: effects on surface
water quality
The cumulative effect of wetlands on
stream water quality and quantity: a
landscape approach
AAA Author
Jing, S.R., Y.F. Lin,
D.Y. Lee, and T.W.'
Wang
Johansson, A.E.,
A.M. Gustavsson,
M.G. Oquist, B.H.
Svensson
Johansson, R., PH.
Gowda, D.J. Mulla,
and B.J. Dalzell
Johansson, R.C.
Johnson, Gary
Johnston, C.A.
Johnston, C.A., N.E.
Detenbeck, and G.J.
Niemi
Pub.
Date
Jan-01
Nov-04
2004
2002
Jul-03
1991
1990
Type
Paper
Paper
PowerPoint
Publisher
Bioresources Technology.
2001Jan;76(2):131-5.
Water Research. 2004
Nov., v. 38, issue 18, p.
3960-3970.
Agricultural Economics,
2004 - ideas.repec.org
Agricultural and Resource
Economics Review, 2002.
Critical Review in
Environmental Control
12:491-565
Biogeochemistry 10:105-
141
Comments
In this paper the authors discuss the results of a study to deter-
mine the ux of methane from a constructed wetland over two
growth seasons on a pilot scale wetland constructed to reduce
nutrient levels in secondary treated wastewater. The emissions
for the spring to autumn period averaged 141 mg CH4 m 2
d 1 (S.D.=187), ranging from consumption of 375 mg CH4 m 2
d 1 to emissions of 1739 mg CH4 m 2d 1 . The spatial and
temporal variations were large, but could be accounted for by
measured environmental factors. Among these factors, sedi-
ment and water temperatures were significant in all cases and
independent of the scale of analysis (r2 up to 0.88).
http://www.sciencedirect.com/science? ob=ArticleURL&
udi=B6V73-4D5JSHK-2&_coverDate=1 1 %2F01 %2F2004&
_alid=375244849&_rdoc=1 &_fmt=&_orig=search&_qd=1 &_
cdi=5831 &_sort=d&view=c&_acct=C000050221 &_version=1 &_
urlVersion=0& userid=1 0&md5=e5a42ee72c1 Of538baOcfa882f
81 5c75
This article presents a modelling system for synthesising het-
erogeneous productivity and nutrient loading potentials inherent
in agricultural cropland for policy use. Phosphorus abatement
cost functions for cropland farmers in a southeastern Minnesota
watershed are metamodelled using frontier analysis. These
functions are used to evaluate policies aimed at reducing non-
point phosphorus discharges into the Minnesota River. Results
indicate an efficiently targeted policy to reduce phosphorus
discharge by 40% would cost US$ $167,700 or $844 per farm.
This article presents a modelling system for synthesising het-
erogeneous productivity and nutrient loading potentials inherent
in agricultural cropland for policy use. Phosphorus abatement
cost functions for cropland farmers in a southeastern Minnesota
watershed are metamodelled using frontier analysis. These
functions are used to evaluate policies aimed at reducing non-
point phosphorus discharges into the Minnesota River. Results
indicate an efficiently targeted policy to reduce phosphorus
discharge by 40% would cost US$ $167,700 or $844 per farm.
2003 National Forum on Water Quality Trading
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#
347
348
349
350
351
352
353
354
355
356
357
358
359
Title
Nutrient dynamics in relation to geo-
morphology of riverine wetlands
Establishing a Framework for Nutrient
Trading in Maryland - A Utility Perspec-
tive
Trading Opportunities and Challenges
for the Wastewater Management Com-
munity
Legal and Financial Liability - Issues in
Mitigation Banking and Water Qual-
ity Trading: A Water Quality Trading
Perspective
Legal and Financial Liability - Issues in
Mitigation Banking and Water Qual-
ity Trading: A Water Quality Trading
Perspective
Nutrient and Sediment Removal by a
Restored Wetland Receiving Agricul-
tural Runoff
Nutrient Chemistry and Hydrology
of Interstitial Water in Brackish Tidal
Marshes of Chesapeake Bay
Nutrient Flux in the Rhode River: Tidal
Exchange of Nutrients by Brackish
Marshes
The Dead Zones: Oxygen-Starved
Coastal Waters
Domestic Wastewater Treatment
through Constructed Wetland in India
The inadequacy of first-order treatment
wetland models
Phosphorus Removal in Emergent Free
Surface Wetlands
Wetlands and Water Quality IN: Wet-
lands Functions and Values; The State
of Our Understanding
AAA Author
Johnston, C.A., S.D.
Bridgham, and J.P
Schubauer-Berigan
Jones, C. and E.
Bacon
Jones, Cyrus
Jones, Cyrus
Washington Subur-
ban Sanitary Com-
mission
Jones, Cyrus
Washington Subur-
ban Sanitary Com-
mission
Jordan, T.E., D.F.
Whigham, K.H.
Hofmockel, and M.A.
Pittek
Jordan, Thomas E.
and David L. Correll
Jordan, Thomas E.,
David L. Correll and
Dennis F. Whigham
Joyce, S.
Juwarkar, A.S., B.
Oke, A. Juwarkar and
S. M. Patnaik
Kadlec, R. H.
Kadlec, R.H.
Kadlec, R.H. and J.A.
Kadlec
Pub.
Date
Mar-
Apr-01
May-98
Jul-03
7/11-
12/2005
7/11-
12/2005
2003
Jul-85
Dec-83
Mar-00
1995
2000
2005
1979
Type
Presentation
PowerPoint
Presentation
Presentation
Paper
Publisher
Soil Science Society of
America journal. Mar/Apr
2001 . v. 65 (2) p. 557-577.
Watershed '98 - Moving
from Theory to Implemen-
tation. Denver, CO. May
5, 1998.
Audio Recording
PowerPoint Presentation
Journal of Environmental
Quality. 2003 Jul-
Aug;32(4):1 534-47.
Estuarine, Coastal and
Shelf Science, Volume
21, Issue 1, July 1985,
Pages 45-55
Estuarine, Coastal and
Shelf Science, Volume
17, Issue 6, December
1 983, Pages 651 -667
Environ Health Perspect.
2000 Mar;108(3):A1 20-5.
PMID: 10706539
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 291 -294
Ecological Engineering
15:105-119.
Journal of Environmental
Science and Health Part
A (2005) 40(6-7): 1293-
306. 2005.
American Water Resourc-
es Assoc., Bethesda, MD
Comments
2003 National Forum on Water Quality Trading
http://www2.eli.org/research/wqt_forum.htm
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking. Describes
some of the challenges involved with implementing waste water
trading programs in light of the Clean Water Act. http://www2.eli.
org/research/wqt_forum.htm
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#
360
361
362
363
364
365
366
367
368
369
370
Title
Temperature Effects in Treatment
Wetlands
Wetlands Treatment Database
Deterministic and Stochastic Aspects
of Constructed Wetland Performance
and Design
Overview: Surface Flow Constructed
Wetlands
Modeling Nutrient Behavior in Wetlands
Treatment Wetlands
Nitrogen Spiraling in Subsurface- ow
Constructed Wetlands: Implications for
Treatment Response
Integrated Natural Systems for Treating
Potato Processing Wastewater
Wetland Use and Impact on Lake
Victoria, Kenya Region
Nitrogen Removal from a Riverine
Wetland: A Field Survey and Simulation
Study of Phragmites japonica
Wastewater Treatment by Tropical
Plants in Vertical- ow Constructed
Wetlands
AAA Author
Kadlec, R.H. and K.R.
Reddy
Kadlec, R.H., R.L.
Knight., S.C. Reed,
and R.W Rubles
(eds.).
Kadlec, Robert H.
Kadlec, Robert H.
Kadlec, Robert H.
and David E. Ham-
mer
Kadlec, Robert H.
and Robert L. Knight
Kadlec, Robert H.,
Chris C. Tanner, Vera
M. Hally, and Max M.
Gibbs
Kadlec, Robert H.,
Peter S. Burgoon and
Michael E. Hender-
son
Kairu, J. K.
Kang, Sinkyu, Kang,
Hojeong Walton,
Dongwook Ko, and
Dowon Lee
Kantawanichkul,
S.,S. Pilaila, W
Tanapiyawanich, W.
Tikampornpittaya,
and S. Kamkrua
Pub.
Date
Sep-Oct
2001
1994
1997
1995
Jan-88
1996
Nov-05
1997
Jul-01
Mar-02
1999
Type
Paper
Publisher
Water Environment
Research. 2001 Sep-
Oct;73(5):543-57.
EPA/600/C-94/200. Office
of Research and Devel-
opment, Cincinnati, OH.
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 149-156
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 1-12
Ecological Modelling, Vol-
ume 40, Issue 1 , January
1 988, Pages 37-66
CRC Press 893 pgs.
Ecological Engineering;
25(4): 365-381 . Nov 2005.
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 263-270
Lakes and Reservoirs:
Research and Manage-
ment, Volume 6, Issue 2,
Page 117-125, Jul 2001
Ecological Engineering;
18(4): 467-475. March 1,
2002.
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 173-178
Comments
This article reports on a study of wetland use and impact on
Lake Victoria conducted in March and April 1995. A field survey
and interviews were used to study wetland use and their impact
on Lake Victoria. This article identifies management issues and
establishes a broad vision for the future. It also addresses the
need to balance the competing demands for wetland use and
development with the need to conserve a healthy and func-
tional Lake Victoria. Investment proposals are made that would
minimize destruction of the wetlands and negative impacts on
the lake. General recommendations for planning and manage-
ment issues, as well as suggestions of specific research needs
that should form the basis of action and investment initiatives,
are given.
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#
371
372
373
374
375
376
377
378
Title
Pollutant Sources Investigation and
Remedial Strategies Development for
the Kaoping River Basin, Taiwan
Water Quality Management in the
Kaoping River Watershed, Taiwan
An Information-theoretical Analysis of
Budget-constrained Nonpoint Source
Pollution Control
Constructed wetland technology and
mosquito populations in Arizona
Multi-Species Plant Systems for
Wastewater Quality Improvements and
Habitat Enhancement
Management of Dairy Waste in the
Sonoran Desert Using Constructed
Wetland Technology
Performance of a sub-surface ow con-
structed wetland in polishing pre-treat-
ed wastewater-a tropical case study
The Dillon Bubble
AAA Author
Kao, C.M., F.C. Wu,
K F Chen T F Lin
YE Yen and PC
Chiang
Kao, C.M., K.F. Chen,
YL. Liao, and C.W
Chen
Kaplan, J.D., R.E.
Howitt YH. Farzin
Karpiscak, M.M., K.J.
Kingsley, R.D. Wass,
FA. Amalfi, J. Friel,
A.M. Stewart, J. Ta-
bor, and J. Zauderer
Karpiscak, Martin M.,
Charles P. Gerba, Pa-
mela M.Watt, Kennith
E. Foster and Jeanne
A. Falabi
Karpiscak, Martin
M., Robert J. Freitas,
Charles P. Gerba,
Luis R. Sanchez and
Eylon Shamir
Kaseva, M.E.
Kashmaniam et. al.
Pub.
Date
2003
2003
2003
Mar-04
1996
1999
Feb-04
1986
Type
Paper
Paper
Paper
Publisher
Water Sci Technol.
2003;48(7):97-103. PMID:
1 4653639
Water Sci Technol.
2003;47(7-8):209-16.
PMID: 12793682
Journal of Environmental
Economics and Manage-
ment, 2003
Journal of Arid Environ-
ments. 2004 Mar., v. 56,
no. 4, p. 681-707.
Water Science and Tech-
nology, Volume 33, Issues
10-11, 1996, Pages
231 -236
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 57-65
Water Research. 2004
Feb., v. 38, no. 3, p. 681-
687.
Comments
This paper analyzes budget-constrained, nonpoint source
(NPS) pollution control with costly information acquisition and
learning, applied to the sediment load management program
for Redwood Creek, which ows through Redwood National
Park in northwestern California. We simulate dynamic bud-
get-constrained management with information acquisition and
learning, and compare the results with those from the current
policy. The analysis shows that when information acquisition in-
creases overall abatement effectiveness the fiscally constrained
manager can reallocate resources from abatement effort to
information acquisition, resulting in lower sediment generation
than would otherwise exist. In addition, with learning about pol-
lution generation occurring over time the manager may switch
from a high intensity of data collection to a lower intensity to
further reduce sediment generation. Also, as sediment control
proceeds at upstream sources, at some time in the future the
marginal reduction in sediment for a given expenditure will
equalize across the sources such that uniform abatement effort
may occur across all sources.
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#
379
380
381
382
383
384
385
Title
Incentive Analysis for Clean Water Act
Reauthorization: Point Source/Nonpoint
Source Trading for Nutrient Discharge
Reductions-Cherry Creek
Contract-Based Trading Programs in
Environmental Regulation
Nitrogen and Bacterial Removal in
Constructed Wetlands Treating Domes-
tic Waste Water
Adult Chloropidae (Diptera) associated
with constructed treatment wetlands
modified by three vegetation manage-
ment techniques
Economic and Environmental Benefits
of Nutrient Trading Programs
In situ ground water denitrification in
stratified, permeable soils underlying
riparian wetlands
Indicators of nitrate in wetland surface
and soil-waters: interactions of vegeta-
tion and environmental factors
AAA Author
Kashmanian, Richard
Apogee Research,
temporary Economic
Keffala, C. and A.
Ghrabi
Keiper, J.B., M.
Stanczak, WE.
Walton
Keiser, M.S. and
Feng Fang
Kellogg, D.Q.,
A.J.Gold, P.M. Groff-
man, K. Addy, M.H.
Stolt, G. Blazejewski
Kennedy, M.P. and
Pub.
Date
1992
Apr-04
Nov-05
Sep-
Oct-03
undated
Mar-
Apr-05
Aug-04
Type
Paper
Draft paper
Paper
Publisher
(Besthesda, MD: Apogee
Research, Inc., 1992),
24-26. Office of Policy,
Planning, and Evalua-
tion, U.S. Environmental
Protection Agency
http://yosemite.epa.
http://aae.agecon.
uga.edu/~akeeler/
Keeler_home/
Working%20papers/Con-
tract-based%20trading.
pdf
Desalination; 185(1-3):
383-389. Nov 2005.
Entomological News.
2003 Sept-Oct, v. 1 1 4, no.
4, p. 205-210.
Environmental Trading
Network and Keiser As-
sociates
Journal of environmental
quality. 2005 Mar-Apr, v.
34, no. 2, p. 524-533.
Hydrology and earth sys-
tem sciences. 2004 Aug.,
v. 8, no. 4, p. 663-672.
Comments
This report examines ef uent trading as one option to achieve
water quality objectives at least cost. While several options are
discussed, the paper focuses principally on trading schemes in
which regulated point sources are allowed to avoid upgrading
their pollution control technology to meet water quality-based
ef uent limits if they pay for equivalent (or greater) reductions
in nonpoint source pollution within their watersheds. The report
identifies several conditions that appear necessary for an
efficient and effective point/nonpoint source trading program.
Reviews of three trading experiences to date-Cherry Creek
and Dillon Reservoir in Colorado, Tar-Pimlico River Basin in
North Carolina-indicate that the absence of one or more of
these necessary conditions result in the delay of trading or will
necessitate a shift in focus of the trading program to facilitate
continued pollutant load reductions. The report also discusses
the economic benefits and costs, the nationwide potential, and
Clean Water Act implications of ef uent trading.
http://www.envtn.org/docs/Japanjiaper.pdf
http://www.copernicus.org/EGU/hess/published papers.html
-------
en
o
#
386
387
388
389
390
391
392
393
394
395
396
Title
Trend Analysis of Nutrient Loading in
the Tar-Pamlico Basin
Treatment of Domestic and Agricultural
Wastewater by Reed Bed Systems
Market-based Approaches and Trading-
Conditions and Examples
Nine Case Studies, Appendices A-l
Cross Cutting Analysis of Trading Pro-
grams: Case Studies in Air, Water and
Wetland Mitigation Trading Systems
Abundance of Alnus incana ssp. rugosa
in Adirondack Mountain Shrub Wet-
lands and Its In uence on Inorganic
Nitrogen
Ecosystem Multiple Markets
Preliminary Economic Analysis of Wa-
ter Quality Trading Opportunities in the
Great Miami River Watershed, Ohio
ETN Paper and Presentation Pre-
sented at the Workshop on Urban
Renaissance and Watershed Manage-
ment, Japan
Water Quality Trading in the United
States: An Overview
Economic and Environmental Benefits
of Water Quality Trading- An Overview
of U.S. Trading Programs
AAA Author
Kennedy, Todd
Kern, Jurgen and
Christine Idler
Kerns, W and K.
Stephenson
Kerr, Robert L, Ste-
ven J.Anderson, and
John Jaksch
Kerr, Robert L.,
Steven J.Anderson,
John Jaksch (Kerr,
Greiner, Anderson
& April and Battelle
Pacific Northwest
Division)
Kiernan, B.D., T.M.
Hurd, and D. J.
Raynal
Kieser & Associates
Kieser & Associates
Kieser, Mark and "An-
drew" Feng Fang
Kieser, Mark S. and
"Andrew" Feng Fang
Kieser, Mark S. and
"Andrew" Feng Fang
Pub.
Date
May-23-
03
Jan-99
Jun-00
Jun-00
Jun-03
Apr-04
Jul-04
Feb-04
Ac-
cessed
Type
Memo
Paper
Case Study
Draft white
paper
Report
Paper
Web-site
Publisher
Memorandum to Michelle
Woolfolf, NC Division of
Water Quality Planning
Branch
Ecological Engineering,
Volume 12, Issues 1-2,
January 1999, Pages
13-25
Kerr, Greiner, Anderson &
April, and Battelle Pacific
Northwest Division
Learning from Innova-
tions in Environmental
Protection, Research
Paper Number 6
Environmental Pollution;
123(3): 347-354. June
2003.
Environmental Trading
Network
Kieser & Associates
Kieser & Associates
The Katoomba Group's
Ecosystem Marketplace
The Environmental Trad-
ing Network and Kieser &
Associates
Comments
This analysis evaluates the trends in nutrient loading in the
Tar-Pamlico Basin from 1991 to 2002 using the Seasonal Ken-
dall test, which tends to perform better than other parametric
methods for data sets that are commonly non-normal, vary sea-
sonally, and contain outliers and censored values. The results
indicate significant, negative trends in ow-adjusted concentra-
tions for both TP and TN. Over the selected study period of
1991-2002, the estimated decrease in TP and TN concentration
over the 12 years are 0.046 mg/L and 0.203 mg/L, respectively.
This represents a reduction of in TP and TN through 2002 of
33% and 18%, respectively, http://h2o.enr.state.nc.us/nps/
TrendGrimesland91 -02prn.pdf
http://www.epa.gov/owowwtr1/watershed/Proceed/kerns.html
http://www.em/tn. org/docs/EMM_WHITE_PAPERApri!04.pdf
Prepared for the Miami Conservancy District, Dayton, Ohio
http://ecosystemmarketplace.com/pages/article.
news.php?component_id=3954&component_version_
id=5625&language_id=12
http://www.em/tn. org/docs/Japan_paper.pdf
mkieser@kieser-associates.com
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#
397
398
399
400
401
402
403
404
405
406
Title
Point/non-point Source Water Quality
Trading for Phosphorus in the Kalama-
zoo River Watershed: A Demonstration
Project
The Challenges of Point/Non-Point
Source Trading
The Challenges of Point/Non-Point
Source Trading
Crunch Time for Water Quality Trading
Will Nutrient Credit Trading Ever Work?
An Assessment of Supply and Demand
Problems and Institutional Obstacles
Science, Technology, and the Changing
Character of Public Policy in Nonpoint
Source Pollution
The Potential for Nitrification and
Nitrate Uptake in the Rhizosphere of
Wetland Plants: A Modelling Study
Seasonal Fluctuations in the Mineral
Nitrogen Content of an Undrained Wet-
land Peat Soil Following Differing Rates
of Fertiliser Nitrogen Application
Constructed Treatment Wetland: A
Study of Eight Plant Species Under
Saline Conditions
Nutrient dynamics of freshwater river-
ine marshes and the role of emergent
macrophytes
AAA Author
Kieser, Mark S. and
David J. Batchelor
King, Dennis Univer-
sity of Maryland
King, Dennis Univer-
sity of Maryland
King, Dennis M. and
Peter J. Kuch
King, Dennis M. and
Peter J. Kuch
King, J.L. and D.L.
Corwin
Kirk, G.J.D. and H.J.
Kronzucker
Kirkham, F.W and
R.J.Wilkins
Klomjeck, P. and S.
Nitisoravut
Klopatek, J. M.
Pub.
Date
1998
7/11-
12/2005
7/11-
12/2005
2005
2003
Sep-05
Jan-15-
93
Feb-05
1978
Type
Presentation
Presentation
Paper
Paper
Publisher
published in the pro-
ceedings for the Water
Environment Research
Foundation Conference
Workshop #1 1 5: Water-
shed-based ef uent trad-
ing demonstration proj-
ects: Results achieved
and lessons learned.
Audio Recording
PowerPoint Presentation
Choices. 20(1): 71 -75.
Environmental Law
Reporter, 33 ELR 10352.
Environmental Law Insti-
tute, Washington, DC.
pg 309-322. In D.L. Cor-
win, K. League, and T.R.
Ellsworth (ed.). Assess-
ment of non-point source
pollution in the vadose
zone. AGU. Washington,
D.C.
Annals of botany. 2005
Sep., v. 96, no. 4, p. 639-
646.
Agriculture, Ecosystems
& Environment, Volume
43, Issue 1,15 January
1993, Pages 11-29
Chemosphere, 58(5):
583-93. Feb 2005
In: Freshwater Wetlands:
Ecological Processes and
Management Potential.
R.E. Good, D.F. Whigham,
and R.L. Simpson, eds.
Academic Press, New
York, NY.
Comments
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqtjnain.htm
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
http://aob.oupjournals.org/
-------
#
407
408
409
410
411
412
413
414
415
416
417
Title
Ancillary benefits and potential
problems with the use of wetlands for
nonpoint source pollution control
Constructed Wetlands for Livestock
Wastewater Management
CREAMS: A Field Scale Model for
Chemicals, Runoff and Erosion from
Agricultural Management Systems
Personal Communication with Scott
Koberg, Idaho Association of Soil Con-
servation Districts
Nutrient, Metal, and Pesticide Removal
During Storm and Nonstorm Events by
a Constructed Wetland on an Urban
Golf Course
Role of Plant Uptake on Nitrogen
Removal in Constructed Wetlands
Located in the Tropics
Comparison of the Treatment Perfor-
mances of Blast Furnace Slag-based
and Gravel-based Vertical Flow Wet-
lands Operated Identically for Domestic
Wastewater Treatment in Turkey
Effectiveness of constructed wetlands
in reducing nitrogen and phosphorus
export from agricultural tile drainage
Assessing Denitrification Rate Limit-
ing Factors in a Constructed Wetland
Receiving Landfill Leachate
The Role of Tradable Permits in Water
Pollution Control
Analysis of Phosphorus Control Costs
and Effectiveness for Point and Non-
point Sources in the Fox-Wolf Basin
AAA Author
Knight, R.L.
Knight, Robert L,
Victor W E. Payne,
Jr., Robert E. Borer,
Ronald A. Clarke, Jr.,
and John H. Pries
Knisel, WG.
Koberg, Scott
Kohler, E.A., V.L
Poole, Z.J. Reicher,
and R.F. Turco
Koottatep, Tham-
marat and Chongrak
Polprasert
Korkusuz, E.
Asuman, Meryem
Bekliolu and Goksel
N. Demirer
Kovacic, D.A., M.B.
David, L.E. Gentry,
K.M. Starks, and R.A.
Cooke
Kozub, D.D. and S.K.
Liehr
Kraemer, R.A., E.
Kampa, and E.
Interwies
Kramer, J., Resource
Strategies, Inc.
Pub.
Date
1992
Jun-00
1980
31-Jan-
06
Dec-04
1997
Feb-05
Jul-Aug-
00
1999
Undated
2003+
Jul-99
Type
Report
Paper
Publisher
Ecological Engineering
1:97-113.
Ecological Engineering;
15(1 -2): 41 -55. June
2000.
USDA Conservation Re-
search Rept. No. 26.
Ecological Engineering;
23(4-5): 285-298. Dec 30,
2004.
Water Science and Tech-
nology, Volume 36, Issue
12, 1997, Pages 1-8
Ecological Engineering;
24(3): 185-198. Feb 20,
2005.
Journal of environmental
quality. July/Aug 2000. v.
29 (4) p. 1 262-1 274.
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 75-82
Ecologic, Institute for In-
ternational and European
Environmental Policy
Fox-Wolf Basin 2000
Comments
This paper explores the use of market-based incentives such as
tradable permits to improve water quality in Chile. http://www.
iadb.org/sds/inwap/publications/Tradable_Permits_in_Water_Pol-
lution_Control.pdf
-------
en
CO
#
418
419
420
421
422
423
424
425
426
427
Title
Analysis of Phosphorus Control Costs
and Effectiveness for Point and Non-
point Sources in the Fox-Wolf Basin
Using a wetland bioreactor to remedi-
ate ground water contaminated with
nitrate (mg/L) and perchlorate (m/L)
Cost-Effective NOx Control in the East-
ern United States
Annual Cycle of Nitrogen Removal by
a Pilot-scale Subsurface Horizontal
Flow in a Constructed Wetland Under
Moderate Climate
Wetland Creation and Restoration: The
Status of the Science
A Comparative Study of Cyperus
papyrus and Miscanthidium violaceum-
based Constructed Wetlands for Waste-
water Treatment in a Tropical Climate
Two Strategies for Advanced Nitrogen
Elimination in Vertical Flow Constructed
Wetlands
Application of Constructed Wetlands for
Wastewater Treatment in Hungary
Applying Lessons Learned from
Wetlands Mitigation Banking to Water
Quality Trading
Potential Nitrate Removal from a River
Diversion into a Mississippi Delta For-
ested Wetland
AAA Author
Kramer, Joseph M.
Resource Strategies,
Inc.
Krauter, PW
Krupnick, A., V. Mc-
Connell, M. Cannon,
T Stoessell, and M.
Batz
Kuschk, P., A.
Wieliner, U. Kappel-
meyer, E. Weilibrodt,
M. Kastner, and U.
Stottmeister
Kusler, J.A. and M.E.
Kentula (eds)
Kyambadde, Joseph,
Frank Kansiime, Lena
Gumaelius, and Gun-
nel Dalhammar
Laber, Johannes,
Reinhard Per er and
Raimund Haberl
Lakatos, Gyula,
Magdolna K. Kiss,
Marianna Kiss and
Peter Juhasz
Landry, Mark,
Antje Siems, Gerald
Stedge, and Leonard
Shabman
Lane, Robert R.,
Hassan S. Mashriqui,
G. Paul Kemp, John
W Day, Jason N. Day,
and Anna Hamilton
Pub.
Date
Jul-99
2001
2000
Oct-03
1990
Jan-04
1997
1997
Feb-05
Jul-03
Type
Report
Discussion
Paper
White paper
Publisher
Fox-Wolf Basin 2000
International Journal of
Phytoremediation.2001.
v. 3(4) p. 415-433.
Resources for the Future
Water Research; 37(1 7):
4236-4242. Oct 2003.
Island Press, Washington,
DC
Water Research; 38(2):
475-485. Jan 2004.
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 71 -77
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 331 -336
Abt Associates Inc.,
Bethesda, MD.
Ecological Engineering;
20(3): 237-249. July 2003.
Comments
A report of a study of the P control costs for non-point (agricul-
tural operations) and point source (municipal treatment plants)
in the Fox-Wolf Basin, Wisconsin. Cost estimates made by
MTP managers. For non-point source, current P loads are
estimated, BMPs are described, and cost estimates are made
for P load reductions. Trading zones recommended because of
non-uniform mixing of P in water bodies. Favorable conditions
for successful trading program include: wide variation in point
source control costs, large number of point sources, availabil-
ity of low cost non-point source reductions. http://www.rs-inc.
com/FWB2K_Final_Report.pdf
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
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#
428
429
430
431
432
433
434
435
436
437
438
Title
Changes in Stoichiometric Si, N and
P Ratios of Mississippi River Water
Diverted Through Coastal Wetlands to
the Gulf of Mexico
The 1994 Experimental Opening of the
Bonnet Carre Spillway to Divert Missis-
sippi River Water into Lake Pontchar-
train, Louisiana
The Role of Plant Uptake on the Re-
moval of Organic Matter and Nutrients
in Subsurface Flow Constructed Wet-
lands: A Simulation Study
Stormwater Quantity and Quality in a
Multiple Pond-wetland System: Flem-
ingsbergsviken Case Study
Quantification of Biofilms in a Sub-Sur-
face Flow Wetland and Their Role in
Nutrient Removal
An Introduction to Water Quality Trad-
ing
Surface Water Nutrient Concentrations
and Litter Decomposition Rates in
Wetlands Impacted by Agriculture and
Mining Activities
Performance of Subsurface Flow
Constructed Wetland Taking Pretreated
Swine Ef uent Under Heavy Loads
Effects of marshes on water quality
Chapter 5: The Pesticide Submodel
Basis for the Protection and Manage-
ment of Tropical Lakes
AAA Author
Lane, Robert
R., John W Day,
Dubravko Justic,
Enrique Reyes, Brian
Marx, Jason N. Day
and Emily Hyfield
Lane, Robert R.,
John W, Day, Jr., G.
Paul Kemp, and Den-
nis K. Demcheck
Langergraber, G.
Larm, Thomas
Larsen, E. and M.
Greenway
Leatherman, J., C.
Smith, and J. Peter-
son
Lee, A.A. and PA.
Bukaveckas
Lee, C.Y., C.C. Lee,
F.Y. Lee, S.K. Tseng,
and C.J. Liao
Lee, G.F., E. Bentley,
and R. Amundson
Leonard, R.A. and
R.D. Wauchope
Lewis, William M. Jr
Pub.
Date
May-04
Aug-01
2005
Jun-00
2004
Aug-04
Dec-02
Apr-04
1975
1980
Mar-00
Type
Paper
Paper
Publisher
Estuarine, Coastal and
Shelf Science; 60(1): 1-
1 0. May 2004.
Ecological Engineering;
17(4): 41 1-422. August
2001.
Water Science and Tech-
nology, 51 (9): 21 3-23.
2005
Ecological Engineering;
15(1 -2): 57-75. June
2000.
Water Science Technol-
ogy. 2004; 49(11-12):
115-22.
Department of Agricul-
tural Economics
Aquatic Botany; 74(4):
273-285. Dec 2002.
Bioresources Technology.
2004 Apr;92(2): 173-9.
In: Coupling of Land and
Water Systems. A.D.
Hasler, Ed., Springer-Ver-
lag, New York, NY.
p. 88-112. In WG. Knisel
(ed.). CREAMS: A field-
scale model for chemi-
cals, runoff and erosion
from agricultural manage-
ment systems. USDA
Conservation Research
Rept. No. 26.
Lakes and Reservoirs:
Research and Manage-
ment, Volume 5, Issue 1,
Page 35-48, Mar 2000
Comments
Prepared for Agricultural Economies' "Risk and Profit" Confer-
ence
http://www.agmanager.info/events/risk_profit/2004/Leatherman-
Peterson.pdf
-------
en
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#
439
440
441
442
443
444
445
446
447
448
Title
Ocean Pollution from Land-based
Sources: East China Sea, China
Spatial Modeling on the Nutrient Reten-
tion of an Estuary Wetland
Roles of Substrate Microorganisms
and Urease Activities in Wastewater
Purification in a Constructed Wetland
System
Comparison of Nutrient Removal Ability
Between Cyperus alternifolius and
Vetiveria zizanioides in Constructed
Wetlands
Phosphorus removal in a wetland con-
structed on former arable land
Temporal and Seasonal Changes in
Greenhouse Gas Emissions from a
Constructed Wetland Purifying Peat
Mining Runoff Waters
The Effect of Heavy Metals on Nitrogen
and Oxygen Demand Removal in Con-
structed Wetlands
Oxygen Demand, Nitrogen and Copper
Removal by Free-water-surface and
Subsurface- ow Constructed Wetlands
Under Tropical Conditions
Removal of solids and oxygen demand
from aquaculture wastewater with a
constructed wetland system in the tart-
up phase
Performance of a constructed wetland
treating intensive shrimp aquaculture
wastewater under high hydraulic load-
ing rate
AAA Author
Li, D. and D. Daler
Li, Xiuzhen, Duning
Xiao, Rob H. Jong-
man, W Bert Harms,
and Arnold K. Bregt
Liang, Wei, Zhen-bin
Wu, Shui-ping Cheng,
Qiao-hong Zhou and
Hong-ying Hu
Liao, X., S. Luo.Y.
Wu, and Z.Wang
Liikanen, A., M.
Puustinen, J. Koski-
aho, T Vaisanen, P.
Martikainen, and H.
Hartikainen
Liikanen, Anu, Jari
T. Huttunen, Satu
Maaria Karjalainen,
Kaisa Heikkinen, Tero
S. Vaisanen, Hannu
Nykanen, and Pertti
J. Martikainen
Lim, P.E., M.G. Tay,
K.Y. Mak, and N.
Mohamed
Lim, P.E., T.F.Wong,
and D.V. Lim
Lin.Y.F, S.R. Jing,
D.Y. Lee, T.W. Wang
Lin.Y.F, S.R. Jing,
D.Y. Lee, Y.F.Chang,
YM. Chen, K.C. Shih
Pub.
Date
Feb-04
Sep-03
Dec-03
Jan-05
May-
Jun-04
Dec-05
Jan-03
May-01
Mar-
Apr-04
Apr-05
Type
Paper
Publisher
Ambio. 2004 Feb;33(1-
2):1 07-13. PMID:
1 5083656
Ecological Modelling;
167(1 -2): 33-46. Sept 1,
2003.
Ecological Engineering;
21 (2-3): 191 -195. Dec 1,
2003.
YingYong Sheng Tai Xue
Bao, 16(1): 156-60. Jan
2005.
Journal of environmental
quality. 2004 May-June, v.
33, no. 3, p. 1124-1132.
Ecological Engineer-
ing, In Press, Corrected
Proof, Available online 15
December 2005
The Science of The Total
Environment; 301(1-3):
13-21. Jan 1,2003.
Environment Interna-
tional; 26(5-6): 425-431 .
May 2001 .
Water Environment Fed-
eration. Mar/Apr 2002. v.
74(2) p. 136-141.
Environmental Pollution.
2005 Apr., v. 134, no. 3, p.
411-421.
Comments
This paper describes the role that steady water discharge from
the Yangtze River has on alleviating impacts from pollution in
the East China Sea and that large-scale water transfer and
dam constructions in the Yangtze River basin will change this
process. The main challenge to restoring ecosystem balance is
to integrate socioeconomic and environmental decision making
in order to promote sustainable development.
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450
451
452
453
454
455
456
457
Title
The Potential Use of Constructed Wet-
lands in a Recirculating Aquaculture
System for Shrimp Culture
Nutrient Removal from Aquaculture
Wastewater Using a Constructed Wet-
lands System
Effects of Macrophytes and External
Carbon Sources on Nitrate Removal
from Groundwater in Constructed
Wetlands
Air/water Exchange of Mercury in the
Everglades II: Measuring and Model-
ing Evasion of Mercury from Surface
Waters in the Everglades Nutrient
Removal Project
Stimulation of microbial sulphate reduc-
tion in a constructed wetland: microbio-
logical and geochemical analysis
In uence of Harvesting on Biogeo-
chemical Exchange in Sheet ow and
Soil Processes in a Eutrophic Flood-
plain Forest
Telephone Interview with Bill Lord,
Neuse River Eduction Team, North
Carolina State University 12/9/2005
Dissolved organic carbon and methane
emissions from a rice paddy fertilized
with ammonium and nitrate
Early development of vascular vegeta-
tion of constructed wetlands in north-
west Ohio receiving agricultural waters
AAA Author
Lin, Ying-Feng,
Shuh-Ren Jing, and
Der-Yuan Lee
Lin, Ying-Feng, Shuh-
Ren Jing, Der-Yuan
Lee, and Tze-Wen
Wang
Lin, Ying-Feng, Shuh-
Ren Jing, Tze-Wen
Wang, and Der-Yuan
Lee
Lindberg, S.E. and H.
Zhang
Lloyd, J.R., D.A.
Klessa, D.L. Parry, P.
Buck, N.L. Brown
Lockaby, B.C., R.G.
Clawson, K. Flynn, R.
Rummer, S. Mead-
ows, B. Stokes and J.
Stanturf
Lord, Bill
Lu,Y, R.Wassa-
mann, H.U. Neue,
and C. Huang
Luckeydoo, L.M., N.R.
Fausey, L.C. Brown,
and C.B. Davis
Pub.
Date
May-03
Jun-02
Oct-02
2-Oct-
00
Apr-04
Feb-97
Nov-
Dec-00
Jan-02
Type
Publisher
Environmental Pollution;
123(1): 107-113. May
2003.
Aquaculture; 209(1-4):
169-184. June 28, 2002.
Environmental Pollution;
1 19(3): 41 3-420. Oct
2002.
Science of the Total
Environment. 2000 Oct
2;259(1-3):1 35-43.
Water Research. 2004
Apr., v. 38, no. 7, p. 1822-
1830.
Forest Ecology and
Management, Volume
90, Issues 2-3, February
1997, Pages 187-194
Journal of environmental
quality. Nov/Dec 2000. v.
29 (6) p. 1733-1740.
Agriculture, ecosystems
& environment. Jan 2002.
v. 88 (1 ) p. 89-94.
Comments
The effect of nitrogen fertilizers on methane (CH4) production
and emission in wetland rice (Oryza sativa L.) is not clearly un-
derstood. Greenhouse pot and laboratory incubation were con-
ducted to determine whether the effect of N type (NH4)-N and
NO3-N) and rate (30 and 120 kg N ha super(-1)) were related to
the availability of carbon for CH4 production in coded rice soils.
The inhibitory effect of NO3-N seemed not fully accountable
for the prolonged reduction in CH4 production and emission in
the fields. The root zone DOC that is enriched by plant-borne C
appears to be a main source for CH4 production and the lower
DOC concentrations with NO3-N application are accountable for
the low CH4 emissions.
http://www.csa. co m/partners/viewrecord.php?requester=gs&coll
ection=TRD&recid=0516433EN&q=Dissolved+organic+carbon+
and+methane+emissions+from+a+rice+paddy+fertilized+with+a
mmonium+and+nitrate&uid=1025630&setcookie=yes
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459
460
461
462
463
464
465
466
467
468
469
470
Title
Nutrient Removal Efficiency and Re-
source Economics of Vertical Flow and
Horizontal Flow Constructed Wetlands
Estimating Denitrification in a Large
Constructed Wetland Using Stable
Nitrogen Isotope Ratios
Efficacy of a Subsurface- ow Wetland
Using the Estuarine Sedge Juncus
kraussii to Treat Ef uent from Inland
Saline Aquaculture
Reducing Phosphorus Loads in Idaho's
Lower Boise River: The Role of Trading
from a State Perspective
Importance of Compliance and En-
forcement in International Emissions
Trading Schemes
Cold-Climate Constructed Wetlands
The Use of Constructed Wetlands for
the Treatment of Run-off and Drainage
Waters: The UK and Ukraine Experi-
ence
mpacts of sedimentation and nitrogen
enrichment on wetland plant commu-
nity development
Nitrogen and phosphorus ux rates
from sediments in a southeastern US
river estuary
Point/non-point Source Trading of Pol-
lution Abatement: Choosing the Right
Trading Ratio
Constructed Wetlands for Wastewater
Treatment in Estonia
Nutrient Dynamics of Riparian Eco-
tones: A Case Study from the Porijogi
River Catchment, Estonia
Application of Constructed Wetlands for
Domestic Wastewater Treatment in an
Arid Climate
AAA Author
Luederitz, Volker,
Elke Eckert, Martina
Lange-Weber, An-
dreas Lange, and
Richard M. Gersberg
Lund, L.J., A.J.
Home, and A.E.Wil-
liams
Lymbery, Alan J.,
Robert G. Doupe,
Thomas Bennett, and
Mark R. Starcevich
Mabe, David
Mace, M. J. (Pro-
gramme Director)
Mashlum, T, P.O.
Jenssen and W S.
Warner
Magmedov, Vy-
acheslav G., Michael
A. Zakharchenko,
Ludmila I.Yakovleva
and Margaret E. Ince
Mahaney, W.M., D.H.
Wardrop, R.P Brooks
Malecki, L.M., J.R.
White and K.R.
Reddy
Malick, A., D. Letson,
and S.R. Crutchfield
Mander, Ulo and Tonu
Mauring
Mander, Ulo, Valdo
Kuusemets and Mari
Ivask
Mandi, L., K.
Bouhoum and N.
Ouazzani
Pub.
Date
Dec-01
Sep-99
Jan-06
Jul-03
3/16-
18/2004
1995
1996
2004
2004
1997
Feb-95
1998
Type
PowerPoint
Presentation
Publisher
Ecological Engineering;
18(2): 157-171. Decem-
ber 2001 .
Ecological Engineering;
14(1 -2): 67-76. Septem-
ber 1999.
Aquacultural Engineering;
34(1): 1-7. Jan 2006.
Foundation for Interna-
tional Law and Develop-
ment
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 95-1 01
Water Science and
Technology, Volume 33,
Issues 4-5, 1996, Pages
315-323
Plant Ecology. 2004, v.
175, no. 2, p. 227-243.
Journal of Environmental
Quality
American J. of Ag. Econ.
7:959-967.
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 323-330
Landscape and Urban
Planning, Volume 31, Is-
sues 1-3, February 1995,
Pages 333-348
Water Science and Tech-
nology, Volume 38, Issue
1 , 1 998, Pages 379-387
Comments
2003 National Forum on Water Quality Trading
http://www.inece.org/emissions/mace.pdf
http://www.kluweronline.com/issn/1385-0237/contents
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471
472
473
474
475
476
477
478
479
480
481
482
Title
Application of a Horizontal Subsurface
Flow Constructed Wetland on Treat-
ment of Dairy Parlor Wastewater
Pollutant Monitoring of Ef uent Credit
Trading Programs For Agricultural
Nonpoint Source Control
The Role of the Submergent Macro-
phyte Triglochin huegelii in Domestic
Greywater Treatment
Final Report: Results of Water-Based
Trading Simulations
Results of Water-Based Trading Simu-
lations
Estimating Erosion in a Riverine Water-
shed: Bayou Liberty-Tchefuncta River
in Louisiana
The Use of Extended Aeration and
In-series Surface- ow Wetlands for
Landfill Leachate Treatment
Interaction and Spatial Distribution of
Wetland Nitrogen Processes
Fate of 15N-nitrate in Unplanted,
Planted and Harvested Riparian Wet-
land Soil Microcosms
Periodic draining reduces mosquito
emergence from free-water surface
constructed wetlands
Producing native and ornamental
wetland plants in constructed wetlands
designed to reduce pollution from
agricultural runoff
Effect of HRT on Nitrogen Removal in
a Coupled HRP and Unplanted Subsur-
face Flow Gravel Bed Constructed
Wetland
AAA Author
Mantovi, Paolo, Marta
Marmiroli, Elena
Maestri, Simona
Tagliavini, Sergio
Piccinini, and Nelson
Marmiroli
March, D.J.
Mars, Ross, Kuruvilla
Mathew and Goen Ho
Marshall, C.
Marshall, Chuck
QEP Philip Services
Martin, A., J.T. Gunt-
er, and J.L. Regens
Martin, Craig D. and
Keith D. Johnson
Martin, Jay F. and K.
R. Reddy
Matheson, F.E.,
M. L.Nguyen, A.B.
Cooper, T.P Burt, and
D.C. Bull
Mayhew, C.R., D.R.
Raman, R.R. Ger-
hardt, R.T Burns, and
M.S. Younger
Maynard, B.K.
Mayo, A.W and J.
Mutamba
Pub.
Date
Jun-03
Nov-00
Jan-99
Sep-99
Sep-99
2003
Jun-05
Dec-97
Oct-02
Mar-
Apr-04
2004
Type
Masters
Thesis
Report
Report
Paper
Publisher
Bioresource Technology;
88(2): 85-94. June 2003.
Virginia Polytechnic and
State University
Ecological Engineering,
Volume 12, Issues 1-2,
January 1999, Pages
57-66
Philip Services, Incorpo-
rated
EPA
Environ Sci Pollut Res Int.
2003;10(4):245-50. PMID:
1 2943008
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 11 9-1 28
Ecological Modelling,
Volume 105, Issue 1,14
December 1997, Pages
1-21
Ecological Engineering;
1 9(4): 249-264. Oct 2002.
Transactions of the
ASAE. 2004 Mar-Apr, v.
47, no. 2, p. 567-573.
Sustainable Agriculture
Research and Education
(SARE) research proj-
ects. Northeast Region.
2001, SARE PROJECT
LNE98-100
Ecological Engineer-
ing, Volume 21, Issues
4-5, 31 December 2003,
Pages 233-247
Comments
http://scholar.lib.vt.edu/theses/available/etd-02142001-091021/
unrestricted/FinalFinalThesisVersion0202.PDF
This study uses spatial analysis techniques and a numerical
modeling approach to predict areas with the greatest sheet ero-
sion potential given different soils disturbance scenarios.
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483
484
485
486
487
488
489
490
491
492
493
494
Title
Nitrogen Transformation in Horizontal
Subsurface Flow Constructed Wetlands
I: Model Development
Nitrogen Transformation in Horizontal
Subsurface Flow Constructed Wetlands
II: Effect of Biofilm
Modelling Nitrogen Removal in a
Coupled HRP and Unplanted Hori-
zontal Flow Subsurface Gravel Bed
Constructed Wetland
Comparative treatment of dye-rich
wastewater in engineered wetland
systems (EWSs) vegetated with differ-
ent plants
Habitat Quality Assessment of Two
Wetland Treatment Systems in the Arid
West-Pilot Study
Habitat Quality Assessment of Two
Wetland Treatment Systems in Missis-
sippi-A Pilot Study
Habitat Quality Assessment of Two
Wetland Treatment Systems in Florida-
-A Pilot Study
Modelling Biofilm Nitrogen Transforma-
tions in Constructed Wetland Meso-
cosms with Fluctuating Water Levels
Cost Effectiveness and Targeting of
Agricultural BMPs for the Tar-Pamlico
Nutrient Trading Program
Nutrient Trading: Experiences and
Lessons
A Guide to Hydrologic Analysis Using
SCS Methods
Multiple Credit Types for a Single
Project Site
AAA Author
Mayo, A.W and T
Bigambo
Mayo, A.W. and T.
Bigambo
Mayo, A.W. and T.
Bigambo
Mbuligwe, S.E.
McAllister, L.S.
McAllister, L.S.
McAllister, L.S.
McBride, Graham B.
and Chris C. Tanner
McCarthy, M., R.
Dodd, J.P Tippett,
and D. Harding
McCatty, T.
McCuen, R.H.
McElwaine, Andrew
Pennsylvania Envi-
ronmental Council
Pub.
Date
2005
2005
2005
Jan-
Feb-05
Jul-92
Nov-92
Nov-93
Sep-99
1996
Aug-99
1982
7/11-
12/2005
Type
Pilot Study
Report
Pilot Study
Report
Proceedings
Case Study
Presentation
Publisher
Physics and Chemistry
of the Earth, Parts A/B/C;
30(1 1-1 6): 658-667. 2005.
Physics and Chemistry
of the Earth, Parts A/B/C;
30(1 1-1 6): 668-672. 2005.
Physics and Chemistry
of the Earth, Parts A/B/C;
30(1 1-1 6): 673-679. 2005.
Water Research. 2005
Jan-Feb, v. 39, issue 2-3
p. 271-280
EPA/600/R-93/117. EPA
Environmental Research
Laboratory, Corvallis, OR
EPA/600/R-92/229. EPA
Environmental Research
Laboratory, Corvallis, OR
EPA/600/R-93/222. EPA
Environmental Research
Laboratory, Corvallis, OR
Ecological Engineering;
14(1 -2): 93-1 06. Septem-
ber 1999.
Watersheds '96. Water
Environment Federation
and U.S. EPA.
Massachusetts Institute
of Technology
Printice-Hall, Inc. Engle-
wood Cliffs, NJ.
PowerPoint Presentation
Comments
This paper discusses some of the technical work that supports
the Tar-Pamlico Nutrient Trading Program implementation. In
order to help the Program participants set a reasonable cost
for trading nitrogen or phosphorus between point and nonpoint
sources and understand how cost effective different best man-
agement practices (BMPs) are, the authors developed cost-
effectiveness estimates (expressed as $/kilogram of nutrient
load reduced) for cost-shared agricultural BMPs in the Basin.
The data represent BMPs that were implemented from 1985 to
1994.
http://www.epa.gov/owowwtr1/watershed/Proceed/mccarthy.html
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#
495
496
497
498
499
500
501
502
503
504
Title
Estimating Inorganic and Organic Ni-
trogen Transformation Rates in a Model
of a Constructed Wetland Purification
System for Dilute Farm Ef uents
Modelling oxygen transport in a reed-
bed-constructed wetland purification
system for dilute ef uents
Watershed-based Pollution Trading
Development and Current Trading
Programs
Relating Net Nitrogen Input in the
Mississippi River Basin to Nitrate Flux
in the Lower Mississippi River: A Com-
parison of Approaches
Soil Organic Matter and Nitrogen
Cycling in Response to Harvesting,
Mechanical Site Preparation, and
Fertilization in a Wetland with a Mineral
Substrate
Stakeholders' View of Watershed-
Based Trading
The Use of Water Quality Trading
and Wetland Restoration to Address
Hypoxia in the Gulf of Mexico
Mosquito (Diptera: Culicidae) develop-
ment within microhabitats of an Iowa
wetland
Water and Mass Budgets of a Verti-
cal- ow Constructed Wetland used for
Wastewater Treatment
Nutrients in salmon hatchery wastewa-
ter and its removal through the use of
a wetland constructed to treat off-line
settling pond ef uent
AAA Author
McGechan, M.B.,
S.E. Moir, G. Sym,
and K. Castle
McGechan, M.B.,
S.E. Moir, I.P.J. Smit,
and K. Castle
McGinnis, S. L.
Mclsaac, G.F., M.B.
David, G.Z. Gertner,
and D.A. Goolsby
Mclaughlin, James
W, Margaret R. Gale,
Martin F. Jurgensen,
and Carl C. Trettin
McNew, Todd
Mehan, G. Tracy III,
Cadmus Group
Mercer, D.R., S.L.
Sheeley, E.J. Brown
Meuleman, Arthur
F. M., Richard Van
Logtestijn, Gerard
B.J. Rijs, and Jos T
A. Verhoeven
Michael, J.H., Jr.
Pub.
Date
May-05
Jun-05
Feb-01
Sept-
Oct/
2002
Apr-00
Jul-03
7/11-
12/2005
Jul-05
Mar-03
Oct-03
Type
Paper
Paper
PowerPoint
Presentation
Publisher
Biosystems Engineering;
91(1): 61 -75. May 2005.
Biosystems Engineering.
2005 June, v. 91, no. 2, p.
1 91 -200.
Springer-Verlag GmbH,
ISSN: 1433-661 8
(Paper) 1434-0852
(Online), DOI: 10.1007/
s1 0022000001 8, Volume
2, Numbers, Pages: 161
-170
J Environ Qual. 2002
Sep-Oct;31(5):1610-22.
PMID: 12371178
Forest Ecology and Man-
agement; 129(1 -3): 7-23.
April 17,2000.
Audio Recording
Journal of Medical Ento-
mology. 2005 July, v. 42,
no. 4, p. 685-693.
Ecological Engineering;
20(1): 31 -44. March 2003.
Aquaculture. 2003 Oct.
31, v. 226, no. 1-4, p.
213-225.
Comments
http://www.sciencedirect.eom/science/journal/1 53751 1 0
This paper describes the diversity of existing pollution trading
programs and the exibility that exists in trading programs to
manage nearly any site-specific watershed pollution problem.
Although the use of watershed-based pollution trading is rela-
tively unproven, observation of the existing trading programs
indicates that trading has the potential to improve water quality
in heavily impaired watersheds, http://www.springerlink.com/
app/home/contribution.asp
The objective of this study was to compare recently published
approaches for relating terrestrial N inputs to the Mississippi
River basin (MRB) with measured nitrate ux in the lower Mis-
sissippi River. Nitrogen inputs to and outputs from the MRB
(1951 to 1996) were estimated from state-level annual agri-
cultural production statistics and NOy (inorganic oxides of N)
deposition estimates for 20 states that comprise 90% of the
MRB. Modeling was used to analyze the data.
2003 National Forum on Water Quality Trading
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqt_main.htm
http://www.elsevier.com/locate/issn/00448486
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505
506
507
508
509
510
511
512
513
Title
Introduction to Market-Based Programs
Market-Based Program Feasibility
Saginaw Basin Modeling
Water Quality Trading Workgroup
Discussion Document. Part XXX. Water
Quality Trading - Draft #20
Rahr Malting Company "Trading" Permit
Watershed-Based Permitting Case
Study: Final Permit Rahr Malting
Company National Pollutant Discharge
Elimination System and State Disposal
System Permit No. MN0031917
A Framework for Trading Phosphorus
Credits in the Lake Allatoona Water-
shed
The Use of Wetlands for Water Pollu-
tion Control in Australia: An Ecological
Perspective
Nitrogen Biogeochemistry in the
Adirondack Mountains of New York:
Hardwood Ecosystems and Associated
Surface Waters
AAA Author
Michigan Department
of Environmental
Quality, Surface Wa-
ter Quality Division
Michigan Department
of Environmental
Quality, Surface Wa-
ter Quality Division
Michigan Department
of Environmental
Quality, Surface Wa-
ter Quality Division
Michigan Department
of Environmental
Quality, Surface Wa-
ter Quality Division
Minnesota Pollution
Control Agency
Minnesota Pollution
Control Agency
Minnesota Pollution
Control Agency
Mitchell, D.S., A.J.
Chick and G.W
Raisin
Mitchell, Myron J.,
Charles T Driscoll,
Shreeram Inamdar,
Greg G. McGee,
Monday O. Mbila, and
Dudley J. Raynal
Pub.
Date
Sep-99
Mar-97
Jan-97
2003
1995
Jun-03
Type
Web site
Web site
Modeling
Discussion
Fact sheet
Case Study
Project plan
Publisher
Michigan Department of
Environmental Quality,
Surface Water Quality
Division
Michigan Department of
Environmental Quality,
Surface Water Quality
Division
Michigan Department of
Environmental Quality,
Surface Water Quality
Division
Michigan Department of
Environmental Quality,
Surface Water Quality
Division
Minnesota Pollution Con-
trol Agency
Minnesota Pollution Con-
trol Agency (MPCA)
River Basin Center Insti-
tute of Ecology, University
of Georgia
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 365-373
Environmental Pollution;
123(3): 355-364. June
2003.
Comments
http://www.deq.state.mi.us/swq/trading/htm/intro.htm
http://www.deq.state.mi.us/swq/trading/htm/kzo.htm
http://www.deq.state.mi.us/swq/trading/htm/wrimod.htm
http://www.deq.state.mi.us/swq/trading/htm/Rule20.htm
http://www.pca.state.mn.us/water/pubs/rahrtrad.pdf
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515
516
517
518
519
520
521
522
Title
Landscape design and the role of
created, restored, and natural riparian
wetlands in controlling nonpoint source
pollution
GLOBAL WETLANDS: OLD WORLD
AND NEW
Wetlands and Lakes as Nitrogen Traps
: Kessler, E. and M. Jansson, eds.
1994. Special Issue of Ambio 23:319-
386. Royal Swedish Academy of Sci-
ences, Stockholm.
Wetlands 3rd Edition
Nitrate-nitrogen Retention in Wetlands
in the Mississippi River Basin
Creating Riverine Wetlands: Ecological
Succession, Nutrient Retention, and
Pulsing Effects
Water Quality Trading in the United
States
Biogeochemical Considerations for
Water Quality Trading in Canada
The Design and Performance of Averti-
cal Flow Reed Bed for the Treatment of
High Ammonia, Low Suspended Solids
Organic Ef uents
AAA Author
Mitsch, WJ.
Mitsch, WJ. (ed.)
Mitsch, William J.
Mitsch, William J. and
James G. Gosselink
Mitsch William J
John W Day, Li
Zhang, and Robert
R. Lane
Mitsch, William J., Li
Zhang, Christopher
J.Anderson, Anne E.
Altor, and Maria E.
Hernandez
Morgan, Cynthia and
Ann Wolverton
Morin, Anne
Morris, Michael and
Robert Herbert
Pub.
Date
1992
1994
Oct-95
21-Jul-
00
Apr-05
Dec-05
Jun-05
2005
1997
Type
Working Paper
Publisher
Ecological Engineering
[ECOL. ENG.].Vol. 1, no.
1-2 pp 27-47 1992
Hardbound ISBN' 0-
444-81 478-7, 992 pages,
publication date: 1994
Ecological Engineering,
Volume 5, Issue 1 , Octo-
ber 1995, Pages 123-1 25
John Wiley and Sons 936
pgs.
Ecological Engineering;
24(4): 267-278. Apr 5,
2005
Ecological Engineering;
25(5)1/19/2006510-527.
Dec. 1 , 2005.
Working Paper # 05-07.
U.S. EPA, National Center
for Environmental Eco-
nomics
Policy Research Initiative
Working Paper, Ottawa.
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 197-204
Comments
General design principles of wetland construction for nonpoint
source (NPS) water pollution control emphasize self-design and
minimum maintenance systems, with an emphasis on function
over form and biological form over rigid designs. These wetlands
can be located as instream wetlands or as oodplain ripar-
ian wetlands, can be located as several wetlands in upstream
reaches or fewer in downstream reaches of a watershed, and
can be designed as terraced wetlands in steep terrain. Case
studies of a natural riparian wetland in southern Illinois, an in-
stream wetland in a downstream location in a northern Ohio wa-
tershed, and several constructed riparian wetlands in northeast-
ern Illinois demonstrate a wide range of sediment and phospho-
rus retention, with greater efficiencies generally present in the
constructed wetlands (63-96% retention of phosphorus) than
in natural wetlands (4-10% retention of phosphorus). By itself,
this could be misleading since the natural wetlands have much
higher loading rates and actually retain an amount of nutrients
comparable to constructed wetlands (1-4 g PI super(2)/year).
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
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524
525
526
527
528
529
530
531
532
533
534
Title
Off-set Banking-A way Ahead for
Controlling Non-point Source Pollution
in Urban Areas
Off-set Banking: A Way Ahead for
Controlling Non-point Source Pollution
in Urban Areas in Georgia
Constructed Wetland for Water Quality
Improvement
Modelling Nutrient Fluxes from Diffuse
and Point Emissions to River Loads:
The Estonian Part of the Transbound-
ary Lake Peipsi/Chudskoe Drainage
Basin (Russia/Estonia/Latvia)
Do wetlands behave like shallow lakes
in terms of phosphorus dynamics?
The Response of a Freshwater Wet-
land to Long-term "Low Level" Nutrient
Loads - Marsh Efficiency
Validation Approaches for Field-, Basin-
, and Regional-scale Water Quality
Models
Effect of NH4+/NO3? Availability on
Nitrate Reductase Activity and Nitrogen
Accumulation in Wetland Helophytes
Phragmites australis and Glyceria
maxima
Information on Water Quality Param-
eters
Simulation of Pollution Buffering Ca-
pacity of Wetlands Fringing the Lake
Victoria
Soil development in phosphate-mined
created wetlands of Florida, USA
Report of the Conservation Innova-
tions Task Force (CITF), Dec. 2003,
Appendix III - Water Quality Trading
- Nonpoint Credit Bank
AAA Author
Morrison, M.
Morrison, Mark D.
Moshiri, G.A.
Mourad, D. and M.
van der Perk
Moustafa, M.Z.
Moustafa, M.Z.,
M.J. Chimney, T.D.
Fontaine, G. Shih and
S. Davis
Mulla, D.J. andT.M.
Addiscott
Munzarova, Edita,
Bent Lorenzen,
Hans Brix, Lenka
Vojtiskova, and Olga
Votrubova
Murphy, S.
Mwanuzi, F, H.
Aalderink, and L.
Mdamo
Nair, V.D., D.A.
Graetz, K.R. Reddy,
and O.G. Olila
National Associa-
tion of Conservation
Districts
Pub.
Date
2003
Jun-02
1993
2004
Feb-00
Sep-96
1999
Jan-06
2005
Apr-03
Jun-01
Dec-03
Type
Paper
Working Paper
Draft
Paper
Report
Publisher
School of Marketing and
Management, Charles
Sturt University
Georgia Water Planning
and Policy Center
CRC Press, Boca Raton,
FL. 1993.
Water Sci Technol.
2004;49(3):21-8. PMID:
1 5053095
Journal of the American
Water Resources Asso-
ciation / Feb 2000. v. 36
(1 ) p. 43-54.
Ecological Engineer-
ing, Volume 7, Issue 1,
September 1996, Pages
15-33
In D.L. Corwin and T.R.
Ellsworth (ed.). Assess-
ment of non-point source
pollution in the vadose
zone. American Geoph-
syical Union. Washington,
D.C. pp. 63-78.
Environmental and Ex-
perimental Botany; 55(1-
2): 49-60. Jan 2006.
USGS Water Quality
Monitoring, BASIN Proj-
ect, City of Boulder, CO
Environmental Interna-
tional. 2003 Apr; 29(1):
95-103.
Wetlands : the Journal
of the Society of the
Wetlands Scientists. June
2001 . v. 21 (2) p. 232-239.
National Association of
Conservation Districts
Comments
http://www.h2opolicycenter.org/pdf_documents/water_working-
papers/2002_004.pdf
http://www.awra.org/jawra/index.html
http://bcn.boulder.co.us/basin/data/BACT/info/ (January 2006).
http://www.nacdnet.org/resources/CITF/app3.htm
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535
536
537
538
539
540
541
542
543
544
545
546
Title
Treatment of Freshwater Fish Farm Ef-
uent Using Constructed Wetlands: The
Role of Plants and Substrate
Soil and Water Assessment Tool User's
Manual
Market and Bargaining Approaches to
Nonpoint Source Pollution Abatement
Problems
Watershed Based Permitting Case
Study: Final Permit
Wetland Project Teaches Students How
To Protect Our Water Supply
Neuse Education Team Impacts: Agri-
cultural Impacts 2: Novel Nursery
Guidance for Phosphorus Offset Pilot
Programs
Seasonal Performance of a Wetland
Constructed to Process Dairy Milk-
house Wastewater in Connecticut
An Environmental Big Stick
The Effects of Stormwater Surface
Runoff on Freshwater Wetlands: A
Review of the Literature and Annotated
Bibliography
Organic Matter Composition, Micro-
bial Biomass and Microbial Activity
in Gravel-bed Constructed Wetlands
Treating Farm Dairy Wastewaters
A Guide to Market-Based Approaches
to Water Quality
AAA Author
Naylor, S., J. Brls-
son, M.A. Labelle, A.
Drizo, andY. Comeau
Neitsch, S.L., J.G.
Arnold, J.R. Kiniry,
and J.R.Williams
Netusil, N.R. and
John B. Braden
Neuse River Compli-
ance Association
Neuse River Eduction
Team
Neuse River Eduction
Team
New York City De-
partment of Environ-
mental Protection,
Bureau of Water
Supply Quality and
Protection
Newman, Jana Majer,
John C. Clausen, and
Joseph A. Neafsey
Newport, Alan
Newton, R.B.
Nguyen, Long M.
Nguyen, T, R.T.
Woodward, M.D. Mat-
lock, and P. Faeth
Pub.
Date
2003
2001
1993
2002
winter
2004
undated
Mar-97
Sep-99
Mar-04
1989
Nov-00
Oct-04
Type
Online
Journal Article
Case Study
Case study
Case study
Guidance Doc
Article
Paper
Publisher
Water Science Technol-
ogy. 2003; 48(5): 215-22.
Available at http://www.
brc.tamus.edu/swat/swat-
2000doc.html.
Water Science and Tech-
nology, 28(3-5), 35-45.
US Environmental Protec-
tion Agency
Neuse River Eduction
Team, North Carolina
State University website.
Viewed on 1 2/05/2005
Neuse River Eduction
Team, North Carolina
State University website.
Viewed on 1 2/05/2005
New York City Depart-
ment of Environmental
Protection, Bureau of
Water Supply Quality and
Protection
Ecological Engineering;
14(1 -2): 181 -198. Sep-
tember 1999.
National Hog Farmer,
PRIMEDIA Busienss
Magazines and Media,
Inc. 2004
Publ. #90-2. The Environ-
mental Institute, Univ. of
Massachusetts, Amherst,
MA
Ecological Engineering;
16(2): 199-221. Novem-
ber 2000.
World Resource Institute
Comments
http://www.epa. gov/npdes/pubs/wq_casestudy_factsht1 1 .pdf
http://www.neuse.ncsu.edu/neusejetters/winter2004/story2.htm
http://www.neuse.ncsu.edu/impact2b.pdf
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547
548
549
550
551
552
553
554
555
556
Title
Evidence of N2O emission and gas-
eous nitrogen losses through nitrifica-
tion-denitrification induced by rice
plants (Oryza sativa L.)
Inhibition kinetics of salt-affected
wetland for municipal wastewater treat-
ment
Wetlands and Water Quality: A Re-
gional Review of Recent Research
in the U.S. on the Role of Freshwater
and Saltwater Wetlands as Sources,
Sinks, and Transformers of Nitrogen,
Phosphorus, and Heavy Metals
Inactivation of Indicator Micro-organ-
isms from Various Sources of Fae-
cal Contamination in Seawater and
Freshwater
A Pilot Study of Constructed Wetlands
Using Duckweed (Lemna gibba L.) for
Treatment of Domestic Primary Ef uent
in Israel
Report of the Proceedings on the
Proposed Neuse River Basin Nutrient
Sensitive Waters (NSW) Management
Strategy
Phase II of the Total Maximum Daily
Load for Total Nitrogen to the Neuse
River Estuary, North Carolina
Neuse River Basinwide Water Quality
Plan
Report of the Proceedings on the
Proposed Neuse River Basin Nutrient
Sensitive Waters (NSW) Management
Strategy. Environmental Management
Commission Meeting
Tar-Pamlico River Nutrient Manage-
ment Plan for Nonpoint Sources of
Pollution
AAA Author
Ni,WZ.,andZ.L. Zhu
Nitisoravut, S. and P.
Klomjek
Nixon, S.W and V.
Lee
Noble, R.T., I.M. Lee,
and K.C. Schiff
Noemi Ran, Moshe
Agami, and Gideon
Oron
North Carolina De-
partment of Environ-
ment and Natural
Resources
North Carolina De-
partment of Environ-
ment and Natural
Resources
North Carolina De-
partment of Environ-
ment and Natural Re-
sources (NCDENR)
North Carolina De-
partment of Environ-
ment, Health and
Natural Resources.
North Carolina Divi-
sion of Environmental
Management, Water
Quality Section
Pub.
Date
Aug-04
Nov-05
1986
Mar-04
May-04
Dec-97
Dec-01
1998
Jun-97
Dec-95
Type
Abstract
Paper
Plan
Plan
Plan
Publisher
Biology and Fertility of
Soils. 2004 Aug., v. 40,
no. 3, p. 211-214.
Water Research. 2005
Nov., v. 39, issue 18, p.
4413-4419.
Technical Rept.Y-86-
2, U.S. Army Corps of
Engineers Waterways
Experiment Station,
Vicksburg, MS
Journal of Applied
Microbiology, Volume 96,
Issue 3, Page 464-472,
Mar 2004
Water Research; 38(9):
2241-2248. May 2004.
Environmental Man-
agement Commission
Meeting December 11,
1997. Printed November
26, 1997
North Carolina Depart-
ment of Environment
and Natural Resources,
Dividion of Water Quality
NC Division of Water
Quality
Reprinted July 1997.
North Carolina Division of
Environmental Manage-
ment, Water Quality
Section
Comments
http://h2o.enr. state, nc.us/ba si nwide/Neuse/neuse_wq_manage-
ment_plan.htm
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557
558
559
560
561
562
563
564
565
566
567
568
Title
Implementation of the Conservation
Partnership's Neuse River Basin Initia-
tive
Tar-Pamlico River Basinwide Water
Quality Plan (July 1999)
North Carolina Division of Water Qual-
ity Nonpoint Source Management Pro-
gram : Tar-Pamlico Nutrient Strategy
Website
Fiscal Analysis: Nonpoint Source
Nutrient Rules Tar-Pamlico River Basin
Nutrient Sensitive Waters Management
Strategy
First Annual Status Report to the Envi-
ronmental Management Commission.
Tar-Pamlico River Nutrient Manage-
ment Plan for Nonpoint Sources
Second Annual Status Report to the
Environmental Management Commis-
sion. Tar-Pamlico River Nutrient Man-
agement Plan for Nonpoint Sources
Point/nonpoint Trading Program for the
Green Bay Remedial Action Plan
The phosphorus index
Evaluation of Phosphorus Retention in
a South Florida Treatment Wetland
Phosphorous Trading in the South Na-
tion River Watershed, Ontario, Canada
Lessons Learned from Point-Nonpoint
Source Trading Case Studies
Lessons Learned from Point-Nonpoint
Source Trading Case Studies
AAA Author
North Carolina Divi-
sion of Soil and Water
Conservation
North Carolina Divi-
sion of Water Quality
North Carolina Divi-
sion of Water Quality
North Carolina Divi-
sion of Water Quality
North Carolina Divi-
sion of Water Quality,
Water Quality Section
North Carolina Divi-
sion of Water Quality,
Water Quality Section
Northeast Wisconsin
Waters For Tomorrow
(now called Fox-Wolf
Basin 2000)
NRCS
Nungesser, M.K. and
M.J. Chimney
O'Grady, D. and M.A.
Wilson
O'Grady, Dennis
South Nation Conser-
vation
O'Grady, Dennis
South Nation Conser-
vation
Pub.
Date
1999
Date ac-
cessed:
12/06/05
Jul. 1,
1999
Oct-97
Jul-98
1994
2001
2001
2002
7/11-
12/2005
7/11-
12/2005
Type
Website
Website
Report
Report
Presentation
Presentation
Publisher
North Carolina Divi-
sion of Soil and Water
Conservation, North
Carolina Department of
Environment and Natural
Resources. Website ac-
cessed 11/26/2005
North Carolina Division of
Water Quality
North Carolina Division of
Water Quality
North Carolina Division of
Water Quality
North Carolina Division
of Water Quality, Water
Quality Section
North Carolina Division
of Water Quality, Water
Quality Section
Northeast Wisconsin Wa-
ters For Tomorrow (now
called Fox-Wolf Basin
2000)
NRCS. Agronomy Techni-
cal Note 26 (revised).
Portland, OR.
Water Science Technol-
ogy. 2001 ;44(1 1-1 2):1 09-
15.
South Nation Conserva-
tion Authority.
Audio Recording
PowerPoint Presentation
Comments
http://www.enr.state.nc.us/DSWC/pages/intitiative.html
http://h2o.enr.state.nc.us/basinwide/tarpam_wq_management_
plan. htm
http://h2o.enr.state.nc.us/nps/tarpam.htm
http://www.envtn.org/wqt/programs/ontario.PDF.
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqtjnain.htm
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqtjnain.htm
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#
569
570
571
572
573
574
575
576
577
Title
Creating Markets for Nutrients and
Other Water Pollutants
Distribution of Nutrients and Heavy
Metals in a Constructed Wetland
System
Mineral nutrition of three aquatic
emergent macrophytes in a managed
wetland in Venezuela
Nonpoint Source-Stream Nutrient Level
Relationships: A Nationwide Study
Reducing Nitrogen from Agriculture at
a River Basin Scale: Lessons Learned
in the Neuse River Basin
Microbial Characteristics of Construct-
ed Wetlands
FerryMon: Using Ferries to Monitor and
Assess Environmental Conditions and
Change in North Carolina's Albemarle-
Pamlico Sound System
Phytoplankton Photopigments as
Indicators of Estuarine and Coastal
Eutrophication
Hydrologic In uence on Stability of Or-
ganic Phosphorus in Wetland Detritus
AAA Author
O'Sullivan, D.
Obarska-Pempkow-
iak, Hanna and Katar-
zyna Klimkowska
Olivares, E., D.
Vizcaino, and A.
Gamboa
Omernik, J.M.
Osmond, Deanna,
Bill Lord, and Mitch
Woodward (NC State
University)
Ottova, Vlasta,
Jarmila Balcarova
and Jan Vymazal
Paerl, Hans and
Thomas Gallo
(Institute of Marine
Science, UNC-Cha-
pel Hill); Christopher
P. Buzzelli (Hollings
Marine Lab); Joseph
S. Ramus, presenter
(Duke University)
Paerl, HansW.
Pant, H.K. and K.R.
Reddy
Pub.
Date
2002
Jul-99
2002
1997
Sep-05
1997
Sep-05
Oct-03
Mar-Apr
2001
Type
Presentation
Presentation
Publisher
Coast-to-Coast 2002
Chemosphere; 39(2):
303-312. July 1999.
Journal of plant nutrition.
2002. v. 25 (3) p. 475-496.
EPA 600/3-79-1 05.
Corvallis Environmental
Research Laboratory,
U.S. EPA, Corvallis, OR.
13th National Nonpoint
Source
Monitoring Workshop
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 11 7-1 23
13th National Nonpoint
Source
Monitoring Workshop
BioScience
Journal of Environmental
Quality. 2001 Mar-
Apr;30(2):668-74.
Comments
http://www.bae. ncsu.edu/programs/extension/wqg/nmp_conf/
presentations.html
http://www.bae. ncsu.edu/programs/extension/wqg/nmp_conf/
presentations.html
http://www.findarticles.com/p/articles/mi_go1 679/is 20031 01
ai_n9292643
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578
579
580
581
582
583
584
585
Title
Planted Riparian Buffer Zones in New
Zealand: Do They Live Up to Expecta-
tions?
Economic and Environmental Impacts
of Nutrient Loss Reductions on Dairy
and Dairy/poultry Farms
Effect of different assemblages of
larval foods on Culex quinquefasciatus
and Culex tarsalis (Diptera: Culicidae)
growth and whole body stoichiometry
The use of design element in wetlands
Hydraulic efficiency of constructed
wetlands and ponds
How Hydrological and Hydraulic Condi-
tions Affect Performance of Ponds
The Role of Plants in Ecologically Engi-
neered Wastewater Treatment Systems
Nitrogen and phosphorus transport
in soil using simulated waterlogged
conditions
AAA Author
Parkyn, Stephanie
M., Rob J. Davies-
Colley, N. Jane Hal-
liday, Kerry J. Costley,
and Glenys F. Croker
Pease, J. and D.E.
Kenyon
Peck, G.W. and WE.
Walton
Persson, J.
Somes, and T H. F.
Wong
Persson, Jesper and
Hans B. Wttgren
Peterson, Susan B.
and John M. Teal
Phillips, I.R.
Pub.
Date
Dec-03
1998
Aug-05
2005
1999
Dec-03
May-96
2001
Type
Paper
Paper
Publisher
Restoration Ecology,
Volume 1 1 , Issue 4, Page
436-447, Dec 2003
Pen State University and
Virginia Tech
Environmental entomol-
ogy. 2005 Aug., v. 34, no.
4 p 767-774
Nordic Hydrology
36(2):113-120.
Water Science and Tech-
nology 40 (3): 291 -300.
Ecological Engineering;
2 1(4-5): 259-269. Dec 31 ,
2003.
Ecological Engineer-
ing, Volume 6, Issues
1 -3, May 1 996, Pages
137-148
Communications in soil
science and plant analy-
sis. 2001 . v. 32 (5/6) p.
821-842.
Comments
Study that assessed nine riparian buffer zone schemes in New
Zealand that had been fenced and planted (age range from 2 to
24 years) and compared them with unbuffered control reaches
upstream or nearby. Included in the study were macroinverte-
brate community composition and a range of physical and water
quality variables within the stream and in the riparian zone.
Generally, streams within buffer zones showed rapid improve-
ments in visual water clarity and channel stability, but nutrient
and fecal contamination responses were variable. Significant
changes in macroinvertebrate communities toward "clean water"
or native forest communities did not occur at most of the study
sites. Improvement in invertebrate communities appeared to
be most strongly linked to decreases in water temperature,
suggesting that restoration of in-stream communities would
only be achieved after canopy closure, with long buffer lengths,
and protection of headwater tributaries. Expectations of ripar-
ian restoration efforts should be tempered by (1) time scales
and (2) spatial arrangement of planted reaches, either within
a catchment or with consideration of their proximity to source
areas of recolonists.
Study of potential N and P losses at edge of farm fields and
root zones in Virginia. Describes details of existing farm-
ing practices. Simulates farm income effects under current
practices and 3 possible nutrient management policies; manure
incorporation, restrict N application, restrict P application. Esti-
mates made by agricultural engineers.
http://www.entsoc.org/pubs/periodicals/ee/index.htm
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586
587
588
589
590
591
592
593
594
595
Title
Factors Affecting Nitrogen Loss in
Experimental Wetlands with Different
Hydrologic Loads
The Interacting Effects of Temperature
and Plant Community Type on Nutrient
Removal in Wetland Microcosms
Legal and Financial Liability - Issues in
Mitigation Banking and Water Quality
Trading: A Wetland Mitigation Banking
Perspective
Design Recommendations for Subsur-
face Flow Constructed Wetlands for
Nitrification and Denitrification
Improved Nitrogen Treatment by Con-
structed Wetlands Receiving Partially
Nitrified Liquid Swine Manure
Swine Wastewater Treatment by Marsh-
pond-marsh Constructed Wetlands
Under Varying Nitrogen Loads
Ammonia volatilization from marsh-
pond-marsh constructed wetlands
treating swine wastewater
Water Quality Trading II: Using Trading
Ratios to Deal With Uncertainties
Hydrodynamic Behavior and Nutrient
Removal Capacity of a Surface-Flow
Wetland
Watershed Protection: Capturing the
Benefits of Nature's Water Supply
Services
AAA Author
Phipps, Richard
G. and William G.
Crumpton
Picard, C.R., L.H.
Fraser, and D. Steer
Platt, George I.
Wetlandsbank, Inc.
Platzer, Christoph
Poach, M. E., P.G.
Hunt, M.B. Vanotti,
K.C. Stone, T.A. Ma-
theny, M.H. Johnson,
and E.J. Sadler
Poach, M.E., P.G.
Hunt, G.B. Reddy,
K.C. Stone, M.H.
Johnson, and A.
Grubbs
Poach, M.E., P.G.
Hunt, G.B. Reddy,
K.C. Stone, T.A. Ma-
theny, M.H. Johnson,
E.J. Sadler
Policy Research
Initiative, Government
of Canada
Polychronopoulos,
Michael and Bronwyn
P. Chapman
Postel, Sandra L.,
Barton H.Thompson,
Jr.
Pub.
Date
Dec-94
Jun-05
7/11-
12/2005
1999
May-03
Nov-04
May-
Jun-04
2001
May-05
Type
Presentation
Conference
Proceeding
Paper Abstract
Paper
Publisher
Ecological Engineer-
ing, Volume 3, Issue 4,
December 1994, Pages
399-408
Bioresources Technol-
ogy, 96(9): 1039-47. June
2005.
Audio Recording
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 257-263
Ecological Engineer-
ing; 20(2): 183-197. May
2003.
Ecological Engineering;
23(3): 165-175. Nov 2004.
Journal of environmental
quality. 2004 May-June, v.
33, no. 3, p. 844-851 .
Sustainable Development
Briefing NOTE, Policy
Research Initiative, Gov-
ernment of Canada
section 1 , chapter 205
World Water Congress
2001, Bridging the Gap:
Meeting the World's
Water and Environmental
Resources Challenges,
World Water and Envi-
ronmental Resources
Congress 2001
Natural Resources Fo-
rum, Volume 29, Issue 2,
Page 98-108, May 2005
Comments
http://www2.eli.org/research/wqt_forum.htm
http://policyresearch.gc.ca/doclib/R2 PRI%20SD%20BN WQII
E.pdf
This paper highlights the relationship between the wetland
hydraulic characteristics and the overall treatment efficiency of
the wetland.
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596
597
598
599
600
601
602
603
604
605
606
Title
Relationship Between Phosphorus Lev-
els in Three Ultisols and Phosphorus
Concentrations in Runoff
The Current Controversy Regarding
TMDLs: Contemporary Perspectives
"TMDLS And
Pollutant Trading"
Soil infiltration and wetland microcosm
treatment of liquid swine manure
National Spatial Crop Yield Simula-
tion Using GIS-based Crop Production
Model
Science and the Protection of Endan-
gered Species
Phosphorus enrichment affects litter
decomposition, immobilization, and
soil microbial phosphorus in wetland
mesocosms.
Transformation of ef uent organic
matter during subsurface wetland treat-
ment in the Sonoran Desert
Water Quality Trading: What Can We
Learn From 10 Years of Wetland Mitiga-
tion Banking?
The Effectiveness of a Small Construct-
ed Wetland in Ameliorating Diffuse
Nutrient Loadings from an Australian
Rural Catchment
Groundwater In uence on the Water
Balance and Nutrient Budget of a
Small Natural Wetland in Northeastern
Victoria, Australia
The Use of Wetlands for the Control of
Non-point Source Pollution
AAA Author
Pote, D.H..TC. Dan-
iel, D.J. Nichols, A.N.
Sharpley, P. A, Moore,
Jr., D.M. Miller, and
D.R. Edwards
Powers, Ann
Prantner, S.R., R.S.
Kanwar, J.C. Lorimor,
and C.H. Pederson
Priva, Satya and
Ryosuke Shibasaki
Pullliam, H.R. and B.
Babbitt
Quails, R.G. and C.J.
Richardson
Quanrud, D.M., M.M.
Karpiscak, K.E. Lan-
sey, and R.G. Arnold
Raffini, Eric and Mor-
gan Robertson
Raisin, G.W, D. S.
Mitchell and R. L.
Croome
Raisin, G., J. Bartley
and R. Croome
Raisin, G.W. and D.
S. Mitchell
Pub.
Date
1999
2003
Jul-01
Jan-01
1997
Mar-
Apr-00
Feb-04
Jul-
Sep-97
Jan-99
1995
Type
Paper
Abstract
Newsletter
Publisher
J. Environ. Qual. 28:170-
175.
VERMONT JOURNAL
OF ENVIRONMENTAL
LAW
Volume Four 2002-2003
Applied Engineering in
Agriculture. July 2001 . v.
1 7 (4) p. 483-488.
Ecological Modelling;
136(2-3): 113-129. Jan
20, 2001 .
Science, 275: 499-500.
Soil Science Society of
America journal. Mar/Apr
2000. v. 64 (2) p. 799-808.
Chemosphere. 2004 Feb.,
v. 54, no. 6, p. 777-788.
National Wetlands
Newsletter; 27(4). Envi-
ronmental Law Institute,
Washington, DC. Jul-Aug
2005. In Press.
Ecological Engineering,
Volume 9, Issues 1-2,
September 1997, Pages
19-35
Ecological Engineering,
Volume 12, Issues 1-2,
January 1999, Pages
133-147
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 177-1 86
Comments
http://www.vjel.org/articles/pdf/powers.pdf
http://www.ped.muni.cz/wgeo/staff/svatonova/AGNPS/ELSE-
VIER/22.htm
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking.
Discusses the opportunities presented by using wetlands in
water quality trading programs and lessons learned from Wet-
land Mitigation Banking that can be applied to development of
nutrient trading programs that use wetlands to generate credits.
http://www2.eli.org/research/wqt_main.htm
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#
607
608
609
610
611
612
613
614
615
Title
Incentive-Based Solutions to Agricul-
tural Environmental Problems: Recent
Developments in Theory and Practice
Nitrogen-fixing Azotobacters from
Mangrove Habitat and Their Utility as
Marine Biofertilizers
Aquatic Plants for Water Treatment and
Resource Recovery
Oxygen transport through aquatic
macrophytes: the role in waster water
treatment
Biogeochemistry of Phosphorus in
Wetlands
Natural Systems for Waste Manage-
ment & Treatment
Wetlands for Wastewater Treatment in
Cold Climates. IN: Future of Water Re-
use, Proceedings of the Water Reuse
Symposium III. Vol. 2:962-972.
Phosphorus retention in small con-
structed wetlands treating agricultural
drainage water.
Nutrient resorption in wetland mac-
rophytes: comparison across several
regions of different nutrient status
AAA Author
Randall, Allen and
Michael A. Taylor
Kathiresan, S. Thade-
dus Maria Ignatiam-
mal, M. Babu Selvam,
and S. Shanthy
Reddy, K.R. and WH.
Smith (eds)
Reddy, K.R., E.M.
D'Angelo, and T.A.
DeBusk
Wetzel, and R.
Kadlec
Reed, S.C., E.J.
Middlebrooks, and
R.W C rites
tian, S. Black, and R.
Reinhardt, M., R.
Gachter, B.Wehrli, B.
Muller
Rejmankova, E.
Pub.
Date
Aug.
2000
Nov-04
1987
1989
2004
1988
1984
05
Aug-05
Type
Paper
Abstract
Abstract
Abstract
Publisher
Journal of Agricultural
and Applied Economics,
32,2(August2000):221-
134, Southern Agricultur-
al Economics Association
Journal of Experimental
Marine Biology and Ecol-
ogy; 312(1): 5-17. Nov
Magnolia Press, Inc.,
Orlando, FL
Journal of Environmental
Quality 19:261-267.
In Phosphorus: Agricul-
ture and the Environ-
ment J. T Sims and A. N.
Sharpley (eds), Soil Sci-
ence Society of America
(In press).
McGraw Hill, New York,
NY
AWWA Research Foun-
dation, Denver, CO
Journal of environmental
quality. 2005 July-Aug, v.
34, no. 4, p. 1251-1259.
New phytologist. 2005
Aug., v. 167, no. 2 p.
471 -482.
Comments
Incentive-based regulatory instruments have the potential to
reduce complinance costs by encouraging efficient resource
allocation and innovation in environmental technology. Cost
reductions from pollution permit trading often have exceeded
expectations, but the devil is in the details: the rules matter. In
recent years, IB instruments of many kinds, from permit trading
to various informal voluntary agreements, have been introduced
in many countries. Point-nonpoint trading programs have been
established in th U.S., but recorded trades have been rare. This
paper speculates about prospects for performance-based moni-
toring of agricultural nonpoint pollution which, we believe, would
encourage trading to the benefit of farmers and society.
http://ideas.repec.0rg/a/jaa/jagape/v32y2000i2p221-34.html
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616
617
618
619
620
621
622
623
624
Title
TMDL Case Study: Tar-Pamlico Basin,
North Carolina
Nitrogen Sources and Gulf hypoxia: Po-
tential for Environmental Credit Trading
Least-cost Management of Nonpoint
Source Pollution: Source Reduction
Versus Interception Strategies for Con-
trolling Nitrogen Loss in the Mississippi
Basin
Pollutant Trading in North Carolina's
River Basins: Tar-Pamlico and Neuse
River Basins
EMC Agenda Item No. 051 1 : TarPam-
lico
Nutrient Sensitive Waters Implementa-
tion Strategy: Phase III
Mechanisms Controlling Phosphorous
Retention Capacity in Freshwater
Wetlands
Use of rhodamine water tracer in the
marshland upwelling system
Lessons Learned from Point-Nonpoint
Source Trading Case Studies
Lessons Learned from Point-Nonpoint
Source Trading Case Studies
AAA Author
Research Traingle
Institute and USEPA,
Office of Wetlands,
Oceans, and Water-
sheds, Watershed
Management Section
Ribaudo, Marc O.,
Ralph Heimlich, and
Mark Peters
Roger Claassen, and
Mark Peters
Rich Gannon (North
Carolina Division of
Water Quality)
Rich Gannon (North
Carolina Division of
Water Quality)
Richardson, C.J.
Richardson, S.D.,
C.S.Willson, K.A.
Rusch
Ringhausen, Alley
Great Rivers Land
Trust
Ringhausen, Alley
Great Rivers Land
Trust
Pub.
Date
undated
2005
May-01
Dec. 7,
2005
Apr-05
1985
Sep-04
7/11-
12/2005
7/11-
12/2005
Type
Case study
Paper
PPt
Implementa-
tion Strategy
Abstract
Presentation
Presentation
Publisher
Total Maximum Daily
Load Program (TMDL),
EPA Office of Water
Quality. Site viewed on
1 1 /9fi/rw
Ecological Economics. 52
(2005) 159-168.
Ecological Economics;
37(2): 183-1 97. May
2001.
Presentation to the Uni-
versity of Pennsylvania
IES Seminar
North Carolina Division of
Water Quality
Science; 228:1 424-1 427.
Ground water. 2004
Sept-Oct, v. 42, no. 5, p.
678-688.
Audio Recording
PowerPoint Presentation
Comments
In recent years, low dissolved oxygen levels, sporadic fish kills,
loss of submerged vegetation, and other water quality problems
have plagued North Carolina's Tar-Pamlico basin. The North
Carolina Division of Environmental Management (NCDEM)
responded by developing stricter nitrogen and phosphorus ef u-
ent standards for dischargers in the basin. However, discharg-
ers were concerned about the high capital costs that might be
required to achieve the nutrient reduction goals. Consequently,
a coalition of dischargers, working in cooperation with the En-
vironmental Defense Fund, the Pamlico-Tar River Foundation,
and NCDEM, proposed a nutrient trading framework through
which dischargers can pay for the development and implemen-
tation of agricultural best management practices (BMPs) to
achieve all or part of the total nutrient reduction goals. The EMC
approved the program in December 1989, at the time this paper
was written, the implementation phase (Phase 1) was currently
under way.
http://www.epa.gov/owow/tmdl/cs1 0/cs1 0.htm
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
Outlines and contrasts the Tar-Pamilco and Neuse River Basin
Nutrient Trading programs.
http://h2o.enr.state.nc.us/nps/documents/PhlllAgreementFinal4-
05.pdf
This document establishes the third phase of a nutrient control
Agreement for point source discharges in the TarPamlico River
Basin, reaffirms loading goals set in Phase II for all sources in
the basin, and proposes timeframes for restoration of nutrient-
related estuarine use support.
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqt_main.htm
Presented at National Forum on Synergies Between Water
Quality Trading and Wetland Mitigation Banking - http://www2.
eli.org/research/wqt_main.htm
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#
625
626
627
628
629
630
631
632
633
634
635
636
637
Title
In uence of Various Water Quality
Sampling Strategies on Load Estimates
for Small Streams
Restored Wetlands as Filters to Re-
move Nitrogen
Lake Allatoona Phase I Diagnostic-fea-
sibility Study Report for 1992-1997
Lower Boise River Ef uent Trading
Demonstration Project: Summary of
Participant Recommendations For a
Trading Framework
Rainfall Simulation Study on the Ef-
fectiveness of Continuous No-till in
Virginia
Constructed Wetlands in Flanders: A
Performance Analysis
Nitrate Removal from Drained and
Re coded Fen Soils Affected by Soil
N Transformation Processes and Plant
Uptake
Nutrient Removal in Subsurface Flow
Constructed Wetlands for Application in
Sensitive Regions
Nitrate removal in riparian wetlands:
interactions between surface ow and
soils
Ammonium production in submerged
soils and sediments: the role of reduc-
ible iron
Organic matter and reducible iron
control of ammonium production in
submerged soils
Nutrient Removal Mechanisms in
Constructed Wetlands and Sustainable
Water Management
Impact of Heavy Metals on Denitrifica-
tion in Surface Wetland Sediments
Receiving Wastewater
AAA Author
Robertson, D.M. and
E.D. Roerish
Romero, Jose A.,
Francisco A. Comin,
and Carmen Garcia
Rose, P.
Ross & Associates
Environmental Con-
sulting, Ltd.
Ross, B.B., PH. Da-
vis, and V.L. Heath
Rousseau, Diederik P.
L, Peter A. Vanrol-
leghem, and Niels De
Pauw
Ruckauf, Ulrike,
Jurgen Augustin, Rolf
Russow and Wolf-
gang Merbach
Rustige, H. and C.
Platzer
Rutherford, J.C. and
M.L. Nguyen
Sahrawat, K.L.
Sahrawat, K.L. and
L.T Narteh
Sakadevan, K. and
H.J. Bavor
Sakadevan, K.,
Huang Zheng and
H.J. Bavor
Pub.
Date
1999
Jul-99
1999
Sep-00
Jun-01
Nov-04
Jan-04
2001
May-
Jun-04
2004
2001
1999
1999
Type
Report
Final Report
Publisher
Water Resources Re-
search 35(1 2):3747-3759.
Chemosphere, Volume
39, Issue 2, July 1999,
Pages 323-332
A.L. Burruss Institute of
Public Service. Kennesaw
State University. Ken-
nesaw, GA.
Idaho Division of Environ-
mental Quality
Ecological Engineering;
23(3): 151-1 63. Nov 2004.
Soil Biology and Bio-
chemistry; 36(1): 77-90.
Jan 2004.
Water Science Technol-
ogy. 2001 ;44(1 1-1 2):1 49-
55.
Journal of environmental
quality. 2004 May-June, v.
33, no. 3, p. 1133-1143.
Communications in Soil
Science and Plant Analy-
sis. 2004, v. 35, no. 3-4, p.
399-41 1 .
Communications in Soil
Science and Plant Analy-
sis. 2001 . v. 32 (9/10) p.
1543-1550.
Water Science and Tech-
nology, Volume 40, Issue
2, 1999, Pages 121 -128
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 349-355
Comments
http://www.deq. state, id. us/water/data_reports/surface_water/tm-
dls/boise_river_lower/boise_river_lower_ef uent_report.pdf
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638
639
640
641
642
643
644
645
646
647
Title
Nutrient dynamics and eutrophication
patterns in a semi-arid wetland: the
effects of uctuating hydrology
Greenhouse-gas-trading Markets
The impact of wetland vegetation dry-
ing time on abundance of mosquitoes
and other invertebrates
Effects of inorganic nitrogen enrich-
ment on mosquitoes (Diptera: Cu-
licidae) and the associated aquatic
community in constructed treatment
wetlands.
Shrimp Pond Ef uent: Pollution Prob-
lems and Treatment by Constructed
Wetlands
Response of an Alaskan Wetland to
Nutrient Enrichment
Investigation of Nitrogen Transforma-
tions in a Southern California Con-
structed Wastewater Treatment Wetland
Performance of a constructed wetland
treating intensive shrimp aquaculture
wastewater under high hydraulic load-
ing rate
Biological diversity versus risk for
mosquito nuisance and disease
transmission in constructed wetlands in
southern Sweden
A New Approach to Water Quality Trad-
ing: Applying Lessons from the Acid
Rain Program in the Lower Boise River
Watershed
AAA Author
Sanchez-Carrillo, S.
and M. Alvarez-Co-
belas
Sandor, R., M.Walsh,
and R. Marques
Sanford, M.R., J.B.
Keiper, W.E.Walton
Sanford, M.R., K.
Chan, W.E.Walton
Sansanayuth, P.,
A. Phadungchep,
S. Ngammontha,
S. Ngdngam, P.
Sukasem, H. Hoshino
and M.S. Ttabucanon
Sanville, William
Sartoris, James J.,
Joan S.Thullen, Larry
B. Barber, and David
E. Salas
Schaafsma, Jennifer
A., Andrew H. Bald-
win, and Christopher
A. Streb
Schafer, M.L., J.O.
Lundstrom, M. Pfef-
fer, E. Lundkvist, J.
Landin
Schary, C. and K.
Fischer-Vanden
Pub.
Date
Oct-01
Aug-02
Dec-03
Sep-05
1996
Mar-88
Sep-99
Sep-99
Sep-07
2004
Type
Paper
Publisher
Water, air, and Soil Pollu-
tion Oct2001. v. 131 (1/4)
p. 97-118.
Philos Transact A Math
Phys Eng Sci. 2002 Aug
15;360(1 797): 1889-900.
Journal of the American
Mosquito Control Asso-
ciation. 2003 Dec., v. 19,
no. 4, p. 361-366.
Journal of medical ento-
mology. 2005 Sept., v. 42,
no. 5, p. 766-776.
Water Science and Tech-
nology, Volume 34, Issue
11, 1996, Pages 93-98
Aquatic Botany, Volume
30, Issue 3, March 1988,
Pages 231 -243
Ecological Engineering;
14(1 -2): 49-65. Septem-
ber 1999.
Ecological Engineering;
14(1 -2): 199-206. Sep-
tember 1999.
Medical and Veterinary
Entomology. 2004 Sept.,
v. 18, no. 3, p. 256-267.
Environmental Practice 6,
no. 4:281-295.
Comments
This paper summarizes the extension of new market mecha-
nisms for environmental services, explains of the importance of
generating price information indicative of the cost of mitigat-
ing greenhouse gases (GHGs) and presents the rationale and
objectives for pilot GHG-trading markets. It also describes the
steps being taken to define and launch pilot carbon markets in
North America and Europe and reviews the key issues related
to incorporating carbon sequestration into an emissions-trading
market.
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#
648
649
650
651
652
653
654
655
656
657
658
Title
Nitrogen Renovation by Denitrification
in Forest Sewage Irrigation Systems
Cost Minimization of Nutrient Reduc-
tion in Watershed Management Using
Linear Programming
Salt Tracer Experiments in Constructed
Wetland Ponds with Emergent Vegeta-
tion: Laboratory Study on the Forma-
tion of Density Layers and Its In uence
on Breakthrough Curve Analysis
Inverse estimation of parameters in a
nitrogen model using field data
Water Quality Characteristics of Veg-
etated Groundwater-fed Ditches in a
Riparian Peatland
The Use of Constructed Wetlands to
Upgrade Treated Sewage Ef uents
Before Discharge to Natural Surface
Water in Texel Island, The Netherlands:
Pilot Study
Phosphorus Loss in Runoff from
Grasslands Related to Soil Test Phos-
phorus and Poultry Litter Application
Market Incentives and Nonpoint Sourc-
es: An Application of Tradable Credits
to Urban Stormwater Management
Treatment of Rainbow Trout Farm
Ef uents in Constructed Wetland with
Emergent Plants and Subsurface Hori-
zontal Water Flow
Effectiveness of a constructed wet-
land for retention of nonpoint-source
pesticide pollution in the lourens river
catchment, South Africa
Nonpoint Source Pollution, Uniform
Control Strategies, and the Neuse
River Basin
AAA Author
Schipper, L.A., WJ.
Dyck, PG. Barton
and PD. Hodgkiss
Schleich, J. and D.
White
Schmid, B.H.,
M.A. Hengl, and U.
Stephan
Schmied, B. and K.
Abbaspour, and R.
Schulin
Scholz, Miklas and
Michael Trepel
Schreijer, M., R.
Kampf, S. Toet and J.
Verhoeven
Schroeder, P.
Schultz, Pati
Schulz, Carsten,
Jbrg Gelbrecht, and
Bernhard Rennert
Schulz, R. and S.K.C.
Peall
Schwabe, K.A.
Pub.
Date
1989
1997
Apr-04
Mar-
Apr-00
Oct-04
1997
2002
Mar-03
Jan-01
2001
Type
Paper
Report
Paper
Publisher
Biological Wastes, Vol-
ume 29, Issue 3, 1989,
Pages 181-187
Water Resources Bulletin;
33(1): 135-1 42. Febru-
ary 1997. Paper Number
95127
Water Resources. 2004
Apr;38(8):2095-102
Soil Science Society of
America Journal. Mar/Apr
2000. v. 64 (2) p. 533-542.
Science of The Total
Environment; 332(1-3):
109-122. Oct 2004.
Water Science and Tech-
nology, Volume 35, Issue
5, 1997, Pages 231 -237
Ph.D. Thesis. University of
Georgia. Athens, GA.
USEPA
Aquaculture; 217(1-4):
207-221. Mar 17, 2003.
Environmental science &
technology. Jan 15, 2001.
v. 35 (2) p. 422-426.
Review of Agricultural
Economics, 2001 - black-
well-synergy.com Page
1 . Review of Agricultural
Economics — Volume 23,
Number 2 — Pages 352-
369
Comments
No abstract available, http://awra.org/~awra/jawra/papers/
J95127.html
Information sheet
This research investigates various policy options considered
by the state of North Carolina for reducing nonpoint source
pollution. Focusing on nitrogen runoff from cropping activi-
ties, we estimate and compare the control costs and estuarine
nutrient loadings under both the initial proposed rules, which
were quite uniform, and the more exible final proposed rules.
We then illustrate the magnitude to which the outcomes from
models and policies can diverge depending upon the treatment
of the application-specific environmental heterogeneity. Such an
analysis illustrates the relative importance of certain types of
heterogeneity associated with the environment on policy design
and real-world outcomes.
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659
660
661
662
663
664
665
666
667
668
669
670
Title
Case Study: Minnesota - Pollutant Trad-
ing at Rahr Malting Co.
Pollutant Trading for Water Quality
Improvement. A Policy Evaluation
Suitability of Constructed Wetlands and
Waste Stabilisation Ponds in Wastewa-
ter Treatment: Nitrogen Transformation
and Removal
Phosphorus retention capacity of filter
media for estimating the longevity of
constructed wetland
A Summary of U.S. Ef uent Trading
and Offset Projects
Nutrient Removal from Piggery Ef uent
Using Vertical Flow Constructed Wet-
lands in Southern Brazil
Past, Present, and Future of Wetlands
Credit Sales
Carbon supply and the regulation of
enzyme activity in constructed wetlands
Nitrogen accumulation in a constructed
wetland for dairy wastewater treatment
Subsurface ow constructed wetland
performance at a Pennsylvania camp-
ground and conference center
Determining the Economic Costs of
Fish Kills for Recreational Users of the
Tar-Pamlico River
The In uence of Rainfall on the Inci-
dence of Microbial Faecal Indicators
and the Dominant Sources of Faecal
Pollution in a Florida River
AAA Author
Senjem, N.
Senjem, N.
Senzia, M.A., D.A.
Mashauri, and A.W
Mayo
Seo, D.C., J.S. Cho,
H.J. Lee, J.S. Heo
Sessions, S. and M.
Leifman.
Sezerino, PH., V.
Reginatto, M.A.
Santos, K. Kayser, S.
Kunst, L.S. Philippi,
and H.M. Scares
Shabman, Leonard
and Paul Scodari
Shackle, V.J., C.
Freeman, and B.
Reynolds
Shamir, E., T.L.
Thompson, M.M. Kar-
piscak, R.J. Freitas,
and J. Zauderer
Shannon, R.D., O.P
Flite, III., and M.S.
Hunter
Sharratt, Jo
Shehane, S.D., V.J.
Harwood, J.E.Whit-
lock, and J.B. Rose
Pub.
Date
11/5-
7/1 997
1997
2003
Jun-05
1999
2003
Dec-04
Nov-00
Apr-01
Nov-
Dec-00
Dec-98
May-05
Type
Case Study
Paper
Report
Paper
Publisher
Environmental Regulatory
Innovations Symposium
Minnesota Pollution Con-
trol Agency, Water Quality
Division
Physics and Chemistry
of the Earth, Parts A/B/C;
28(20-27): 11 17-1 124.
2003.
Water Research. 2005
June, v. 39, issue 11 , p.
2445-2457.
Prepared for Dr. Mahesh
Podar, U.S. Environmen-
tal Protection Agency,
Office of Water
Water Science Technol-
ogy. 2003; 48(2): 129-35.
Discussion Paper 04-48
Resources for the Future,
Washington DC
Soil Biology & Biochemis-
try. Nov2000. v. 32(13) p.
1935-1940.
Journal of the American
Water Resources As-
sociation / Apr 2001 . v. 37
(2) p. 315-325.
Journal of environmental
quality. Nov/Dec 2000. v.
29 (6) p. 2029-2036.
Department of Eco-
nomics, East Carolina
University
Journal of Applied
Microbiology, Volume 98,
Issue 5, Page 1127-1136,
May 2005
Comments
http://www.pca.state.mn.us/hot/es-mn-r.html
http://www.epa.gov/owow/watershed/hotlink.htm
Not peer reviewed
http://www.rff.org/documents/rff-dp-04-48.pdf
http://www.awra.org/jawra/index.html
Results of a survey of recreational river users. The results
of the survey are used to make an estimate of the decrease
in consumer surplus (monetary value of river recreation) as
a result of declining water quality. The report describes the
results as being similar to the published results of other studies.
http://www.ecu.edu/econ/ecer/sharratt.pdf
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#
671
672
673
674
675
676
677
678
679
680
681
Title
Treatment of high-strength winery
wastewater using a subsurface- ow
constructed wetland
Stability of phosphorus within a
wetland soil following ferric chloride
treatment to control Eutrophication
Planning to Protect Water Resources
and Natural Areas: A Comparison of
the Water Basin Management Strate-
gies of the Chesapeake Bay and the
Netherlands
Simulation of nitrogen and phos-
phorus leaching in a structured soil
using GLEAMS and a new submodel,
"PARTLE."
Seasonal Effect on Ammonia Nitrogen
Removal by Constructed Wetlands
Treating Polluted River Water in South-
ern Taiwan
An Examination of Key Elements and
Conditions for Establishing a Water
Quality Trading Bank
Assessing the Efficacy of Dredged
Materials from Lake Panasoffkee,
Florida: Implication to Environment and
Agriculture. Part 1 : Soil and Environ-
mental Quality Aspect
Ammonium Removal in Constructed
Wetlands with Recirculating Subsurface
Flow: Removal Rates and Mechanisms
Vegetation is the main factor in nutri-
ent retention in a constructed wetland
buffer
Microbial Immobilisation of Added Ni-
trogen and Phosphorus in Constructed
Wetland Buffer
Nutrient requirements of seven plant
species with potential use in shoreline
erosion control
AAA Author
Shepherd, H.L., M.E.
Grismer, and G.
Tchobanoglous
Sherwood, L.J. and
R.G. Quails
Shingara, Erica
Shirmohammadi,
A., B. Ulen, L. F.
Bergstrom, and W G.
Knisel
Shuh-Ren Jing and
Ying-Feng Lin
Siems, Antje, Jenny
Ahlen, and Mark
Landry
Sigua, G.C., M.L.
Holtkamp, and S.W
Coleman
Sikora, F.J., Zhu
Tong, L. L. Behrends,
S. L. Steinberg and H.
S. Coonrod
Silvan, N., H.Va-
sander, J. Laine
Silvan, Niko, Harri
Vasander, Marjut
Karsisto, and Jukka
Laine
Sistani, K.R. and D.A.
Mays
Pub.
Date
Jul-Aug-
01
Oct-01
Apr-01
1998
Jan-04
Mar-05
2004
1995
Jan-04
Oct-03
2001
Type
Master's
Project
White paper
Paper
Publisher
Water environment
research : a research
publication of the Water
Environment Federation.
July/Aug 2001 . v. 73 (4) p.
394-403.
Environmental science &
technology. Oct 15, 2001.
v. 35(20) p. 4126-4131.
Department of City and
Regional Planning, Uni-
versity of North Carolina
at Chapel Hill
Transactions of the
ASAE, 41 (2):353-360.
Environmental Pollution;
127 (2): 291 -301. Jan
2004.
Abt Associates Inc.,
Bethesda, MD.
Environ Sci Pollut Res Int.
2004; 11 (5): 32 1-6. PMID:
1 5506635
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 193-202
Plant and soil. 2004
Jan., v. 258, no. 1-2, p.
179-187.
Applied Soil Ecology;
24(2): 143-1 49. Oct 2003.
Journal of plant nutrition.
2001 . v. 24 (3) p. 459-467.
Comments
Both the Chesapeake Bay and the Neatherlands face similar
threats and challenges with respect to water quality and man-
agement planning. This paper compares management strate-
gies used to protect water resources and natural areas in both
locations, http://www.planning.unc.edu/carplan/mpshingara.pdf
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
Study to quantify the effect of applied lake dredged materials
on soil physico-chemical properties (soil quality) at the disposal
site. The experimental treatments that were evaluated consisted
of different proportions of lake dredged materials at 0, 25, 50,
75, and 100%. The study demonstrated that when lake dredged
materials were incorporated into existing topsoil they would
have the same favorable effects as liming the field.
http://www.kluweronline.com/issn/0032-079X/contents
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682
683
684
685
686
687
688
689
690
691
Title
Ancillary benefits of wetlands con-
structed primarily for wastewater
treatment
Constructed Wetlands as Nitrogen
Sinks in Southern Sweden: An Empiri-
cal Analysis of Cost Determinants
Constructed wetlands as a sustainable
solution for wastewater treatment in
small villages
The Origins, Practice, and Limits of
Emissions Trading
Seasonal and Annual Performance of
a Full-Scale Constructed Wetland Sys-
tem for Sewage Treatment in China
Role of Scirpus lacustris in Bacterial
and Nutrient Removal from Wastewater
Nutrient Cycling at the Sediment-Water
Interface and in Sediments at Chirica-
hueto Marsh: A Subtropical Ecosystem
Associated with Agricultural Land Uses
S-1004: 2003 Annual Meeting
Soil Phosphorus in Isolated Wetlands
of Subtropical Beef Cattle Pastures
The Effects of Season and Hydro-
logic and Chemical Loading on Nitrate
Retention in Constructed Wetlands: A
Comparison of Low- and High-Nutrient
Riverine Systems
AAA Author
Slather, J.H.
Sbderqvist, Tore
Solano, M.L., P. So-
riano, M.P Ciria
Solomon, Barry D.
(Barry David)
Song, Zhiwen,
Zhaopei Zheng, Jie
Li, Xianfeng Sun,
Xiaoyuan Han, Wei
Wang, and Min Xu
Soto, R, M. Garcia,
E. de Luis and E.
Becares
Soto-Jimenez, M. R,
R. Paez-Osuna, and
H. Bojorquez-Leyva
Southern Asso-
ciation of Agricultural
Experiment Station
Directors
Sperry, C.M.
Spieles, Douglas J.
and William J. Mitsch
Pub.
Date
1998
Aug-02
Jan-04
1995
Jan-06
1999
Reb-03
2003
2004
Sep-99
Type
Paper
Minutes
Abstract
Publisher
In: D.A. Hammer (ed.)
Constructed Wetlands for
Wastewater Treatment,
Municipal, Industrial and
Agricultural. Lewis Pub-
lishers, Chelsea, Ml.
Ecological Engineering;
19(2): 161-1 73. Aug 2002.
Biosystems engineering.
2004 Jan., v. 87, no. 1, p.
109-118.
Journal of Policy History;
14(3):293-320. 2002.
Ecological Engineer-
ing, In Press, Corrected
Proof, Available online 4
January 2006
Water Science and Tech-
nology, Volume 40, Issue
3, 1999, Pages 241 -247
Water Research; 37(4):
719-728. Re b 2003.
Southern Association of
Agricultural Experiment
Station Directors
Master's Thesis, Univer-
sity of Rlorida. 2004.
Ecological Engineering;
14(1 -2): 77-91. Septem-
ber 1999.
Comments
http://www.sciencedirect.eom/science/journal/1 53751 1 0
This paper is an examination of how emissions trading pro-
grams evolved as an unintended consequence of the Clean Air
Act of 1970. Despite some early theoretical work by economists,
most precedent-setting decisions were made as regulators,
firms, environmental groups, and policy analysts struggled to
address practical issues of implementation associated with the
Clean Air Act. Today, after almost three decades of practice and
theory having refined one another, the ability of program design-
ers and policy analysts to anticipate and address the challenges
of specific trading applications has significantly improved.
However, some early decisions resulted in precedents that have
never received the level of deliberation and debate they warrant.
http://www.lgu. umd.edu/lgu_v2/pages/reportMeet/1 58_min.doc
http://www.archbold-station.org/ABS/publicationsPDR/Sperry-
2004-thesis.pdf
-------
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CD
#
692
693
694
695
696
697
698
699
700
701
Title
Emissions of Greenhouse Gases
from Ponds Constructed for Nitrogen
Removal
Monitoring and modeling lateral trans-
port through a large in situ chamber
Pollutant Trading Guidance
Nonpoint Source Management Plan
Transaction Costs and Tradable Permits
The Next Generation of Market-Based
Environmental Policies
SCS Runoff Equation Revisited for
Variable Source Runoff Areas
Does Batch Operation Enhance
Oxidation in Subsurface Constructed
Wetland?
In uence of Nutrient Supply on Growth,
Carbohydrate, and Nitrogen Metabolic
Relations in Typha angustifolia
Toward an Effective Watershed-Based
Ef uent Allowance Trading System:
Identifying the Statutory and Regula-
tory Barriers to Implementation
AAA Author
Stadmark, Johanna
and Lars Leonardson
Starr, J.L., A.M. Sa-
deghi, Y.A. Pachepsky
State of Idaho, De-
partment of Environ-
mental Quality
State of Idaho, Divi-
sion of Environmental
Quality
Stavins, Robert N.
Stavins, Robert
N.and Bradley W
Whitehead
Steenhuis, T.S., M.
Winchell, I. Rossing,
J.A. Zollweg, and M.F.
Walter
Stein, O.R., PB.
Hook, J.A. Bieder-
man, W.C.Allen, and
D.J. Borden
Steinbachova-
Vojtiskova, Lenka,
Edita Tylova, Ales
Soukup, Hana
Hana Novicka, Olga
Votrubova, Helena
Lipavska, and Hana
i kova
Stephenson, K., L.
Shabman, and L.L.
Geyer
Pub.
Date
Dec-05
Nov-
Dec-05
Nov-03
Dec-99
1995
Nov-96
1995
2003
Aug-05
1999
Type
Draft
Report
Paper
Paper
Publisher
Ecological Engineer-
ing;25(5):542-551. Dec.
1 , 2005.
Soil Science Society of
America journal. 2005
Nov-Dec, v. 69, no. 6, p.
1871-1880.
State of Idaho, Depart-
ment of Environmental
Quality
State of Idaho, Division of
Environmental Quality
Journal of Environmental
Economics and Manage-
ment, 29, 133-148.
Resource Economics, 1 1 ,
571-585.
Discussion Paper 97-10
Prepared for Environ-
mental Reform: The Next
Generation
Project, Daniel Esty and
Marian Chertow, editors,
Yale Center
for Environmental Law
and Policy.
J. of Irrigation and Drain-
age Eng. ASCE 121:234-
238.
Water Science Technol-
ogy. 2003;48(5): 149-56.
Environmental and
Experimental Botany, In
Press, Corrected Proof,
Available online 2 August
2005
Environmental Lawyer,
Vol.5, Pp. 775-815, 1999
Comments
http://www.deq. state. id. us/water/prog_issues/waste_water/pollut-
antjrading/polluta nt_tradingjguidance_entire.pdf
http://www.deq. Idaho. gov/water/data_reports/surface_water/nps/
management_plan_entire.pdf
http://www.rff.org/rff/Documents/RFF-DP-97-10.pdf
-------
oo
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#
702
703
704
705
706
707
708
Title
Market Based Strategies and Nutrient
Trading: What You Need to Know (563
KB)
Freshwater Wetlands, Urban Storm-
water, and Nonpoint Pollution Control:
A Literature Review and Annotated
Bibliography (2nd Ed.)
Spatial variability in palustrine wetlands
Comparison of soil and other environ-
mental conditions in constructed and
adjacent palustrine reference wetlands
Marsh-Pond-Marsh Constructed Wet-
land Design Analysis for Swine Lagoon
Wastewater Treatment
Assessing TMDL Effectiveness Us-
ing Flow-adjusted Concentrations: A
Case Study of the Neuse River, North
Carolina
The Use of Wetlands for Controlling
Stormwater Pollution
AAA Author
Stephenson, Kerns
and Shabman
Stockdale, E.G.
Stolt, M.H., M.H.
Genthner, WL. Dan-
iels, and V.A. Groover
Stolt, M.H., M.H.
Genthner, WL.
Daniels, V.A. Groover,
S. Nagle, and K.C.
Haering
Stone, K.C., M.E.
Poach, PG. Hunt, and
G.B. Reddy
Stow, C.A. and M.E.
Borsuk
^trprkpr F W 1 M
OUClslxCI, Q.VV., J.lvl.
Kersnar, E.D. Driscoll
and R.R. Horner
Pub.
Date
Nov-95
1991
Mar-
Apr-01
Dec-00
Oct-04
May-15-
03
Apr-92
Type
Report
Bibliography
Paper
Abstract
Publisher
Department of Agri-
cultural and Apprlied
Economics, Virginia
Tech, Blacksburg, VA and
Virginia Division of Soil
and Water Conservation,
Department of Conserva-
tion and Recreation
WA Department of Ecol-
ogy, Olympia, WA
Soil Science Society of
America journal. Mar/Apr
2001 . v. 65 (2) p. 527-535.
Wetlands : the journal
of the Society of the
Wetlands Scientists. Dec
2000. v. 20 (4) p. 671 -683.
Ecological Engineering;
23(2): 127-133. Oct 1,
2004
Environ Sci Technol. 2003
May 15;37(10):2043-50
The Terrene Inst., Wash-
ington, DC
Comments
Addresses policy tools that can be used to better achieve the
dual objectives of improved environmental quality and more
exible, cost-effective environmental policies.
In this paper, the authors propose the use of" ow-adjusted"
pollutant concentrations to evaluate the effectiveness of man-
agement actions taken to meet approved TMDLs. Pollutant con-
centrations are usually highly correlated with stream ow, and
ow is strongly weather-dependent. Thus, pollutant loads, which
are calculated as pollutant concentration multiplied by stream-
ow, have a large weather-dependent variance component. This
natural variation can be removed by calculating ow-adjusted
concentrations. While such values are not a direct measure of
pollutant load, they make it easier to discern changes in stream-
water quality. Additionally, they are likely to be a better predic-
tor of pollutant concentrations in the receiving waterbody. We
demonstrate the use of this technique using long-term nutrient
data from the Neuse River in North Carolina. The Neuse River
Estuary has suffered many eutrophication symptoms, and a
program to reduce nutrient loading has been in place for several
years. We show that, in addition to revealing recent reductions
in nutrient inputs, annual ow-adjusted riverine nutrient concen-
trations show a more pronounced relationship with estuarine
nutrient concentrations than do annual nutrient loads. Thus, we
suggest that the calculation of ow-adjusted concentrations is a
useful technique to aid in assessment of TMDL implementation.
http://www.ncbi. nlm.nih.gov/entrez/query.fcgi?cmd=Retrieve&db
=PubMed&list_uids=12785506&dopt=Abstract
-------
#
709
710
711
712
713
714
715
716
717
718
719
720
721
Title
Aquaculture Sludge Removal and Sta-
bilization within Created Wetlands
Enhanced Removal of Organic Matter
and Ammoniacal-nitrogen in a Column
Experiment of Tidal Flow Constructed
Wetland System
Watershed-scale simulation of
sediment and nutrient loads in Georgia
Coastal Plain streams using the an-
nualized AGNPS model
Natural Wastewater Treatment in
Hungary
Characterization of oxidation-reduction
processes in constructed wetlands for
swine wastewater treatment
Seasonal dynamics of nutrients and
physico-chemical conditions in a con-
structed wetland for swine wastewater
treatment
Water Quality Trading: Nonpoint Credit
Bank Model
Charting the Course: The Comprehen-
sive Conservation and Management
Plan for Tampa Bay
The Tampa Bay Nitrogen Management
Consortium Action Plan 1995 - 1999
Plants as Ecosystem Engineers in Sub-
surface- ow Treatment Wetlands
Growth and nutrient dynamics of soft-
stem bulrush in constructed wetlands
treating nutrient-rich wastewaters.
Plants for constructed wetlands -A
comparison of the growth and nutrient
uptake characteristics of eight emer-
gent species
Linking Pond and Wetland Treatment:
Performance of Domestic and Farm
Systems in New Zealand
AAA Author
Summerfelt, Steven
T, Paul R.Adler,
D. Michael Glenn
and Ricarda N.
Kretschmann
Sun, Guangzhi,
Yaqian Zhao and
Stephen Allen
Suttles, J.B., G.Vel-
lidis, D.D. Bosch, R.
Lowrance, J.M. Sheri-
dan, E.L. Usery
Szabo, A., A. Oszto-
ics, and F. Szilagyi
Szogi, A.A., PG.
Hunt, E.J. Sadler,
D.E. Evans
Szogi, A.A., PG.
Hunt, F.J. Humenik,
K.C. Stone, J.M. Rice,
and .E.J. Sadler
Talbert, Gerald
Tampa Bay National
Estuary Program
Tampa Bay Nitrogen
Management Consor-
tium. Partnership for
Progress.
Tanner, C.C.
Tanner, C.C.
Tanner, C.C.
Tanner, C.C. and J.P
Sukias
Pub.
Date
Jan-99
Jan-06
Sep-
Oct-03
2001
Mar-04
1994
No date
Dec-96
Mar-98
2001
2001
1996
2003
Type
Paper
Plan
Plan
Publisher
Aquacultural Engineer-
ing, Volume 19, Issue
2, January 1999, Pages
81-92
Journal of Biotechnology;
115(2): 189-197. Jan 26,
2005.
Transactions of the
ASAE. 2003 Sept-Oct, v.
46, no. 5, p. 1325-1335.
Water Science Technolo-
gy. 2001 ;44(1 1 -1 2):331 -8.
Applied Engineering in
Agriculture. 2004 Mar., v.
20, no. 2, p.1 89-200.
ASAE Paper #94-2602.
National Association of
Conservation Districts.
Tampa Bay National
Estuary Program
Tampa Bay Nitrogen
Management Consortium.
Partnership for Progress.
Water Science Technol-
ogy. 2001 ;44(1 1 -1 2):9-1 7.
Wetlands Ecology and
Management. 9: 49-73
Ecological Engineering 7:
59-83.
Water Science Technol-
ogy. 2003;48(2): 331-9.
Comments
Background information for the National Forum on Synergies
Between Water Quality Trading and Wetland Mitigation Banking
- http://www2.eli.org/research/wqt_main.htm
-------
#
722
723
724
725
726
727
728
729
730
731
732
Title
Constructed wetlands in New Zealand-
Evaluation of an emerging "natural"
wastewater treatment technology
Relationships between loading rates
and pollutant removal during matura-
tion of gravel-bed constructed wetlands
Using Constructed Wetlands to Treat
Subsurface Drainage From Intensively
Grazed Dairy Pastures in New Zealand
Nutrient Removal by a Constructed
Wetland Treating Subsurface Drainage
from Grazed Dairy Pasture
Plants for Constructed Wetland Treat-
ment Systems - A Comparison of the
Growth and Nutrient Uptake of Eight
Emergent Species
Effect of Water Level Fluctuation on
Nitrogen Removal from Constructed
Wetland Mesocosms
Effect of Loading Rate and Planting on
Treatment of Dairy Farm Wastewaters
in Constructed Wetlands-ll. Removal of
Nitrogen and Phosphorus
Nitrogen Processing Gradients in
Subsurface- ow Treatment Wetlands:
In uence of Wastewater Characteristics
Tradable Discharge Permits System for
Water Pollution of the Upper Nanpan
River, China
Developing Cost-Effective Geographic
Targets for Nitrogen Reductions in the
Long Island Sound Watershed
An Evaluation of Pollutant Removal
from Secondary Treated Sewage Ef-
uent Using a Constructed Wetland
System
AAA Author
Tanner, C.C., J.P.S.
Sukias, and C. Dall
Tanner, C.C., J.P.S.
Sukias, and M.P
Upsdell
Tanner, C.C., M.L.
Nguyen, and J.P.
Sukias
Tanner, C.C., M.L.
Nguyen, and J.P.S.
Sukias
Tanner, Chris C.
Tanner, Chris C.,
Joachim D'Eugenio,
Graham B. McBride,
James P. S. Sukias
and Keith Thompson
Tanner, Chris C.,
John S. Clayton and
Martin P. Upsdell
Tanner, Chris C.,
Robert H. Kadlec,
Max M. Gibbs, James
PS. Sukias, and M.
Long Nguyen
Tao, Wendong,
WeiminYang, and Bo
Zhou
Tedesco, M. and P.
Stacey
Thomas, PR., P.
Glover and T Kala-
roopan
Pub.
Date
2000
1998
2003
Jan-05
Sep-96
Jan-99
Jan-95
Mar-02
May-03
Jun-96
1995
Type
Proceedings
of Water 2000:
Guarding
the Global
Resource
Conference,
Auckland,
March 19-23.
Paper
Proceedings
Publisher
CD ROM ISBN 1-877134-
30-9, New Zealand Water
and Wastes Association.
Journal of Environmental
Quality 27: 448-458.
Water Science Technol-
ogy. 2003;48(5):207-1 3.
Agriculture, Ecosystems
& Environment; 105(1-2):
145-162. Jan 2005.
Ecological Engineer-
ing, Volume 7, Issue 1,
September 1996, Pages
59-83
Ecological Engineering,
Volume 12, Issues 1-2,
January 1999, Pages
67-92
Water Research, Volume
29, Issue 1 , January
1 995, Pages 27-34
Ecological Engineering;
18(4): 499-520. March 1,
2002.
Watersheds '96. Water
Environment Federation
and U.S. EPA
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 87-93
Comments
http://www.idrc.org.sg/uploads/user-S/10536118430ACF64.pdf
. http://www.epa.gov/owowwtr1 /watershed/Proceed/tedesco.htm
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oo
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#
733
734
735
736
737
738
739
740
741
Title
Denitrification in an estuarine head-
water creek within an agricultural
watershed
Managing Vegetation in Surface- ow
Wastewater-treatment Wetlands for
Optimal Treatment Performance
Effects of Vegetation Management in
Constructed Wetland Treatment Cells
on Water Quality and Mosquito Produc-
tion
Tradable Permit Approaches to Pollu-
"Introduction." Pp. xi-xxviii in Emissions
Trading Programs. Volume I. Implemen-
tation and Evolution
Constructed Wetlands as Recirculation
Filters in Large-scale Shrimp Aquacul-
The Utilization of a Freshwater Wetland
for Nutrient Removal from Secondarily
Treated Wastewater Ef uent
Cost-Effectiveness of Agricultural
BMPs for Nutrient Reduction in the Tar-
Pamlico Basin
Cost-Effectiveness of Agricultural
BMPs for Nutrient Reduction in the Tar-
Pamlico River Basin (NC)
AAA Author
Thompson, S.P, M.F.
Piehler, and H.W
Paerl
Thullen, Joan S.,
James J. Sartoris,
and S. Mark Nelson
Thullen, Joan S.,
James J. Sartoris,
and William E.Walton
Tietenberg, T
Tietenberg, T.
Tilley, David Rogers,
Harish Badrinaray-
anan, Ronald Rosati,
and Jiho Son
Tilton, D.L. and R.H.
Kadlec
Tippet, J. and R.
Dodd Research
Triangle Institute
Tippett, John P. and
Randall C. Dodd
Pub.
Date
Dec-00
Dec-05
Mar-02
2000
2001
Jun-02
1979
Jan-95
Jul-95
Type
Abstract
Paper
Summary of a
Paper
Publisher
Journal of environmental
quality. Nov/Dec 2000. v.
29(6) p. 1914-1923.
Ecological Engineering;
25(5): 583-593. Dec 2005.
Ecological Engineering;
18(4): 441 -457. March 1,
2002.
In: Kaplowitz, M.D. (ed.)
Property Rights, Econom-
ics, and the Environment.
JAI Press Inc., Stanford,
Connecticut.
Aldershot, England: Ash-
gate Publishing Limited.
Aquacultural Engineering;
26(2): 81 -109. June 2002.
Journal of Environmental
Quality; 8:328-334. 1979.
North Carolina Depart-
ment of Environment,
Health, and Natural
Resources
Project Spotlight,
NWQEP Noted, The
NCSU Water Quality
Group Newsletter. North
Carolina Cooperative
Extension Service, North
Carolina State University,
College of Agricultural
and Life Sciences. Num-
ber 72, July 1995, ISSN
1062-9149
Comments
This paper discusses some of the technical work that supports
the Tar-Pamlico Nutrient Trading Program implementation. In
order to help the Program participants set a reasonable cost
for trading nitrogen or phosphorus between point and nonpoint
sources and understand how cost effective different best man-
agement practices (BMPs) are, the authors developed cost-
effectiveness estimates (expressed as $/kilogram of nutrient
load reduced) for cost-shared agricultural BMPs in the Basin.
The data represent BMPs that were implemented from 1985 to
1994.
Evaluates the cost-effectiveness of Agricultural BMPs. The
authors did not include the cost-effectiveness of restoring and
protecting riparian areas and wetlands in their analysis and
indicated additional research is needed on this subject.
http://www.bae.ncsu.edu/programs/extension/wqg/issues/72.
html
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#
742
743
744
745
746
747
748
749
750
751
752
753
754
Title
Nitrogen Fixation Associated with
Juncus balticus and Other Plants of
Oregon Wetlands
Nutrient Removal through Autumn
Harvest of Phragmites australis and
Typha latifolia Shoots in Relation to
Nutrient Loading in a Wetland System
Used for Polishing Sewage Treatment
Plant Ef uent
The Functioning of a Wetland System
Used for Polishing Ef uent from a Sew-
age Treatment Plant
Biological Control of Water Pollution
Quantifying Nitrogen Retention in Sur-
face Flow Wetlands for Environmental
Planning at the Landscape-scale
Hydrologic characterization of two prior
converted wetland restoration sites in
eastern North Carolina
The Effects of NH4+ and NO3? on
Growth, Resource Allocation and
Nitrogen Uptake Kinetics of Phragmites
australis and Glyceria maxima
Natural Wetlands and Urban Stormwa-
ter: Potential Impacts and Management
Subsurface Flow Constructed Wetlands
for Wastewater Treatment: A Technol-
ogy Assessment
Process Design Manualu Constructed
Wetlands and Aquatic Plant Systems
for Municipal Wastewater Treatment
Report on the Use of Wetlands for
Municipal Wastewater Treatment and
Disposal
Freshwater Wetlands for Wastewater
Management Environmental Assess-
ment Handbook
The Effects of Wastewater Treatment
Facilities on Wetlands in the Midwest
AAA Author
Tjepkema, J.D. and
H.J. Evans
Toet, S., M. Bouw-
man, A. Cevaal, and
J.T.A. Verhoeven
Toet, Sylvia, Richard
S.P van Logtestijn,
Michiel Schreijer,
Ruud Kampf, and Jos
T.A. Verhoeven
Tourbier, J. and R.W
Pierson (eds)
Trepel, Michael and
Luca Palmeri
Tweedy, K.L. and R.O.
Evans
Tylova-Munzarova,
Edita, Bent Lorenzen,
Hans Brix, and Olga
Votrubova
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
U.S. EPA
Pub.
Date
1976
2005
Jul-05
1976
Aug-02
Sep-
Oct-01
Apr-05
Feb-93
Jul-93
Sep-88
Oct-87
Sep-85
1983
Type
Abstract
Abstract
Abstract
Abstract
Abstract
Abstract
Abstract
Publisher
Soil Biology and Bio-
chemistry, Volume 8,
Issue 6, 1976, Pages
505-509
Journal of Environmental
Science and Health Part
A (2005) 40(6-7): 11 33-
1156
Ecological Engineering;
25(1 ): 101-1 24. Jul 20,
2005.
Univ. of Pennsylvania
Press, Philadelphia, PA
Ecological Engineering;
19(2): 127-1 40. Aug 2002.
Transactions of the
ASAE. Sept/Oct 2001 . v.
44 (5) p. 1135-1142.
Aquatic Botany; 81 (4):
326-342. Apr 2005.
EPA843-R-001 . Office of
Wetlands, Oceans and
Watersheds, Washington,
DC
EPA832-R-93-001 . Office
of Water, Washington, DC
EPA 625/1 -88/022.
Center for Environmental
Research Information,
Cincinnati, OH
EPA 430/09-88-005. Of-
fice of Municipal Pollution
Control, Washington, DC
EPA 904/9-85-1 35. Re-
gion IV, Atlanta, GA
EPA 905/3-83-002. Re-
gion V, Chicago, IL
Comments
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#
755
756
757
758
759
760
761
762
763
764
765
766
Title
Constructed Wetlands for Wasterwater
Treatment and Wildlife Habitat: 17 Case
Studies
The Ecological Impacts of Wastewater
on Wetlands, An Annotated Bibliogra-
phy
Preliminary Review for a Geographic
and Monitoring Program Project: A
Review of Point Source-Nonpoint
Source Ef uent Trading/Offset Systems
in Water Sheds
Health Threats Grow from Tons of
Manure
The Phosphorus Index: A Phosphorus
Assessment Tool
Bank Review and Certification Require-
ments: A Wetland Mitigation Banking
Perspective
Constructed wetlands bibliography
Assessing a Neural Network Modeling
Approach for Predicting Nutrient Loads
in the Mahantango Watershed
Water Quality Training
Water Quality Trading Assessment
Handbook: EPA Region 10's Guide to
Analyzing Your Watershed
National Water Quality Trading Assess-
ment Handbook
Water Quality Trading Assessment
Handbook: EPA Region 10's Guide to
Analyzing Your Watershed
AAA Author
U.S. EPA
U.S. EPA/U.S. F&WL
Service
U.S. Geological
Service
Unger, H.
United States Depart-
ment of Agriculture,
Natural Resources
Conservation Service
Urban, David T
Land and Water
Resources, Inc.
US Department of
Agriculture
US Department of
Agriculture: Agri-
cultural Research
Service
US Environmental
Protection Agency
US Environmental
Protection Agency
US Environmental
Protection Agency
US Environmental
Protection Agency
Pub.
Date
1993
1984
Jun-05
2002
Aug-94
7/11-
12/2005
2000
Ac-
cessed
Aug-00
Jul-03
Nov-04
Jul-03
Type
Abstract
Open file
report 03-79
Report
Presentation
Web-site
fact sheet
Handbook
Handbook
Publisher
EPA 832-R-93-005. Office
of Wastewater Manage-
ment, Washington, DC.
EPA 905/3-84-002.
Region V, Chicago, IL and
U.S. F&WL Service, Kear-
neysville, WY
U.S. Geological Service
Atlanta Journal Constitu-
tion. November 24, 2002.
United States Department
of Agriculture, Natural
Resources Conservation
Service
PowerPoint Presentation
Ecological Sciences
Division of the Natural
Resources Conserva-
tion Service and the
Water Quality Information
Center at the National
Agricultural Library
US Department of
Agriculture: Agricultural
Research Service
US Environmental Protec-
tion Agency
EPA910-B-03-003, 100
pgs
EPA841-B-04-001
EPA910-B-03-003, 100
pgs
Comments
http://pubs.usgs.gov/of/2003/of03-079/WoodjDFR03-79.pdf
http://www.nrcs.usda.gov/technical/ECS/nutrient/pindex.html
http://www.nal. usda.gov/wqic/Constructed_Wetlands_all/index.
html (January 2006).
http://www.ars.usda.gov/research/projects/projects.htm7accn
no=410035
A newsletter acknowledging the importance of nutrient trading
in meeting reduction goals, the process the nutrient trading
negotiation team underwent to reach consensus, and a listing
of the recommended fundamental principles and elements of a
trading program.
http://www.epa.gov/OWOW/watershed/trading.htm
http://yosemite.epa.gov/R10/OI.NSF/
34090d07b77d50bd88256b79006529e8/
642397cf31d9997388256d66007d53a7?OpenDocument
http://www.epa.gov/owow/watershed/trading/handbook/
http://yosemite.epa.gov/R10/OI.NSF/
34090d07b77d50bd88256b79006529e8/
642397cf31d9997388256d66007d53a7?OpenDocument
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#
767
768
769
770
771
772
773
774
775
776
777
778
Title
National Water Quality Trading Assess-
ment Handbook
Shepherd Creek, OH Case Study
National Management Measures to
Protect and Restore Wetlands and
Riparian Areas for the Abatement of
Nonpoint Source Pollution
Sharing the Load: Ef uent Trading for
Indirect Dischargers
The Twenty Needs Report: How
Research Can Improve the TMDL
Program
Improving Air Quality with Economic
Incentive Programs
Better Assessment Science Integrating
Non-Point Sources (BASINS)
Polluted Runoff (Nonpoint Source Pol-
lution): Clean Water Act Section 319
Introduction to the Clean Water Act
Guiding Principles for constructed
Treatment Wetlands: Providing for Wa-
ter Quality and Wildlife Habitat
Manual: Constructed Wetlands Treat-
ment of Municipal Wastewaters
Free Water Surface Wetlands for
Wasterwater Treatment: A Technology
Assessment
AAA Author
US Environmental
Protection Agency
US Environmental
Protection Agency
US Environmental
Protection Agency
US Environmental
Protection Agency,
New Jersey Depart-
ment of Environmen-
tal Protection, and
Passaic Valley Sewer-
age Commissioners
US Environmental
Protection Agency,
Office of Water
US EPA
US EPA
US EPA
US EPA
US EPA
US EPA
US EPA
Pub.
Date
Nov-04
Jul-05
May-98
2002
2001
2003
Oct-05
Mar-03
Oct-00
2000
1999
Type
Handbook
Web page
Paper
Report
Website
Website
Publisher
EPA841-B-04-001
US Environmental Protec-
tion Agency
EPA841-B-05-003, US
Environmental Protection
Agency Office of Water,
Washington, DC. July
2005.
U.S. EPA, Office of Policy
Planning and Evaluation,
with New Jersey Depart-
ment of Environmental
Protection and Passaic
Valley Sewerage Com-
missioners.
EPA-231-R-98-003
EPA841-B-02-002, US
Environmental Protection
Agency Office of Water,
Washington DC (43 pp).
2002.
Office of Air and Radia-
tion. EPA-425/R-01 -001 .
US EPA
US EPA, Office of Water.
October, 2005.
US EPA, Watershed
Academy Web. March
2003.
Office of Wetlands,
Oceans and Watersheds.
Washington, DC, EPA
843-B-00-003, October
2000.
EPA/625/R-99/010. Office
of Research and Devel-
opment, Cincinnati, OH.
EPA832-S-99-001.0ffice
of Wastewater Manage-
ment, Washington, DC.
Comments
http://www.epa.gov/owow/watershed/trading/handbook/
http://www.epa.gov/owow/nps/wetmeasures/
http://www.epa. gov/owow/tmdl/20needsreport_8-02.pdf
http://www.epa.gov/ostwater/BASINS/index.html.
http://www.epa.gov/owow/nps/cwact.html. Home page for the
Clean Water Act Section 319 with links and information on
grants, case studies and policy directions.
http://www.epa.gov/watertrain/cwa/index.htm. Online tutorial on
the Clean Water Act.
Introduces guiding principles for planning, sitting, design, con-
struction, operation, maintenance and monitoring of constructed
treatment wetlands. Provides information on current Agency
policies, permits, regulations and resources.
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779
780
781
782
783
784
785
786
787
788
789
790
791
792
Title
Section 319 Nonpoint Soucre Program
Success Story, North Carolina, Tar-
Pamlico Basin Agricultural Manage-
ment Strategy
Endenton Stormwater Wetland Project:
Wetland Systems Reduce Nitrogen
Concentrations
Nutrient Profiles in the Everglades:
Examination Along the Eutrophication
Gradient
Simulation of the Effects of Nutrient
Enrichment on Nutrient and Carbon
Dynamics in a River Marginal Wetland
A Model of Carbon, Nitrogen and
Phosphorus Dynamics and Their Inter-
actions in River Marginal Wetlands
Carbon, nitrogen and phosphorus cy-
cling in river marginal wetlands; model
examination of landscape geochemical
ows
Soil nitrogen dynamics in organic and
mineral soil calcareous wetlands in
eastern New York
Nitrogen Removal in Constructed Wet-
lands Treating Nitrified Meat Process-
ing Ef uent
An Operational Survey of a Natural
Lagoon Treatment Plant Combining
Macrophytes and Microphytes Basins
Emergent Plant Decomposition and
Sedimentation: Response to Sediments
Varying in Texture, Phosphorus Content
and Frequency of Deposition
Impact of drying and re-wetting on N, P
and K dynamics in a wetland soil
Nutrient Dynamics in Minerotrophic
Peat Mires
Evolving Environmental Policies
and Asset Values: Nutrient Trading
Schemes In The Netherlands
Horizontal Sub-surface Flow and Hy-
brid Constructed Wetlands Systems for
Wastewater Treatment
AAA Author
US EPA, Office of
Water Quality
US EPA, Office of
Water Quality
Vaithiyanathan, P. and
C.J. Richardson
Van der Peijl, M. J.,
M.M.P Van Oorschot,
and J.T.A. Verhoeven
Van der Peijl, M.J.
and J.T.A. Verhoeven
van der Peijl, M.J.
and J.T.A. Verhoeven
Van Hoewyk, D., P.M.
Groffman, E. Kiviat,
G. Mihocko, and G.
Stevens
van Oostrom, A.J.
Vandevenne, Louis
Vargo, Sharon M.,
Robert K. Neely and
Stephen M. Kirkwood
Venterink, H., T.E.
Davidsson, K. Kiehl,
L. Leonardson
Verhoeven, J.T.A.
Vukina, T. and A.
Wossink
Vymazal, Jan
Pub.
Date
Jul-05
Ac-
cessed
7-Oct-
97
Oct-00
Jun-99
Jul-00
Nov-
Dec-00
1995
1995
Aug-98
Jun-02
1986
6/25-
27/1 998
Dec-05
Type
Case Study
Publisher
US EPA, Office of Water
Quality, EPA841-F-05-
0048
Section 319 Success
Stories, Vol. Ill
Science of the Total
Environment. 1997 Oct
7;205(1):81-95.
Ecological Modelling;
134(2-3): 169-1 84. Octo-
ber 30, 2000.
Ecological Modelling;
11 8(2-3): 95-1 30. June
15, 1999.
Biogeochemistry. July
2000. v. 50(1) p. 45-71.
Soil Science Society of
America journal. Nov/Dec
2000. v. 64 (6) p. 2168-
2173.
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 137-1 47
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 79-86
Environmental and
Experimental Botany, Vol-
ume 40, Issue 1 , August
1 998, Pages 43-58
Plant and soil. June 2002.
v. 243(1) p. 119-130.
Aquatic Botany, Volume
25, 1986, Pages 117-137
World Congress of Envi-
ronmental and Resource
Economists, Venice,
Ecological Engineering;
25( 5): 478-790. Dec. 1 ,
2005.
Comments
http://www.epa.gov/nps/Success319/state/ncJar.htm
http://www.kluweronline.com/issn/0032-079X/contents
no copy or abstract found
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#
793
794
795
796
797
798
799
800
801
Title
The Use of Sub-surface Constructed
Wetlands for Wastewater Treatment in
the Czech Republic: 10 Years Experi-
ence
Constructed Wetlands for Wastewater
Treatment in the Czech Republic the
First 5 Years Experience
Constructed Wetlands for Wastewater
Treatment in the Czech Republic: State
of the Art
Nutrient Trading: Harnessing Com-
merce as a Tool to Control Water
Pollution
Vegetation management to stimulate
denitrification increases mosquito
abundance in multipurpose constructed
treatment wetlands
Phosphorus Credit Trading in the
Cherry Creek Basin: An Innovative
Approach
Phosphorus Credit Trading in the Kal-
amazoo River Basin: Forging Nontradi-
tional Partnerships
Phosphorus Credit Trading in the Fox-
Wolf Basin: Exploring Legal, Economic,
and Technical Issues
Nitrogen Credit Trading in Maryland:
A Market Analysis for Establishing a
Statewide Framework
AAA Author
Vymazal, Jan
Vymazal, Jan
Vymazal, Jan
Wall, Roland
Walton, WE. and J.A.
Jiannino
Water Environment
Research Foundation
Water Environment
Research Foundation
Water Environment
Research Foundation
Water Environment
Research Foundation
Pub.
Date
Jun-02
1996
1995
un-
known
Mar-06
2000
2000
2000
2002
Type
Report
Paper
Paper
Paper
Paper
Publisher
Ecological Engineering;
18(5): 633-646. June
2002.
Water Science and Tech-
nology, Volume 34, Issue
11, 1996, Pages 159-164
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 357-364
Academy of Natural Sci-
ences Web site
Journal of the American
Mosquito Control Asso-
ciation. 2005 Mar., v. 21,
no. 1 , p. 22-27.
Water Environment Re-
search Foundation
1 30 pages. Soft cover.
Water Environment Re-
search Foundation
282 pages. Soft cover.
Water Environment Re-
search Foundation
1 1 0 pages. Soft cover.
Water Environment Re-
search Foundation
90 pages. Soft cover.
Comments
http://www.acnatsci.org/education/kye/pp/kye7152004.html
Comprehensively documents the development and implementa-
tion of the Cherry Creek Basin Water Quality Authority's trading
program in Denver, Colorado, while highlighting several other
trading programs. By identifying the similarities and differences
in program design and linking those key elements to scien-
tific, economic, and institutional conditions in the watershed
community, this report examines some lessons, guidelines,
and patterns emerging from the growing field of trading. Paper
available for purchase at: http://www.werf.org/AM/Template.
cfm?Section=Research_Profile&Template=/CustomSource/Re-
search/PublicationProfile.cfm&id=97-IRM-5a
Describes a program of watershed-based trading intended to
reduce phosphorus and sediment loading in selected reaches of
the Kalamazoo River in Michigan. Examines the environmental
and economic benefits of trading between point and nonpoint
sources. Identifies policy issues and technical design elements
vital to the design of a statewide water quality trading program.
Describes the pursuit of watershed-based trading by Fox -Wolf
Basin 2000, a nonprofit watershed alliance in northeastern Wis-
consin. Examines the region's history of water quality problems,
analyzes legal and economic issues connected with trades, and
describes preliminary work commenced in each basin toward
establishment of total maximum daily loads.
This report explores whether a market for nitrogen credits could
help wastewater treatment plants in Maryland achieve cost-ef-
fective water quality objectives. The results of this study indicate
that, compared with approaches that require all plants to attain
equal nitrogen concentrations, trading options could achieve the
same environmental objectives while saving millions of dollars.
Non-WERF subscribers can order hard copies of this report
for $65.00 each plus postage and handling. To order copies,
contact David Morroni at 703-684-2470.
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#
802
803
804
805
806
807
808
809
810
811
Title
Nitrogen Credit Trading in the Long
Island Sound Watershed
Phosphorus Credit Trading in the Kal-
amazoo River Basin: Forging Nontradi-
tional Partnerships
Modelling the Impact of Historical Land
Uses on Surface-water Quality Using
Groundwater Flow and Solute-transport
Models
Laboratory assessment of atrazine and
uometuron degradation in soils from a
constructed wetland
In situ removal of dissolved phosphorus
in irrigation drainage water by planted
oats: preliminary results from growth
chamber experiment
Fundamental Processes Within Natural
and Constructed Wetland Ecosystems:
Short-term Versus Long-term Objec-
tives
Impacts of Freshwater Wetlands on
Water Quality: A Landscape Perspec-
tive
Nitrification and denitrification rates
of everglades wetland soils along a
phosphorus-impacted gradient
In uence of selected inorganic electron
acceptors on organic nitrogen mineral-
ization in Everglades soils
In uence of phosphorus loading on
organic nitrogen mineralization of
everglades soils
AAA Author
Water Environment
Research Foundation
Water Environmental
Research Foundation
Wayland, Karen G.,
David W Hyndman,
David Boutt, Bryan C.
Pijanowski, and David
T Long
Weaver, M.A., R.M.
Zablotowicz, M.A.
Locke
Wen, L. and F. Reck-
nagel
Wetzel, R.G.
Whigham, D.F., C.
Chitterling, and B.
Palmer
White, J.R. and K.R.
Reddy
White, J.R. and K.R.
Reddy
White, J.R. and K.R.
Reddy
Pub.
Date
2002
2000
Sep-02
Nov-04
Jun-02
2001
1988
Nov-
Dec-03
May-
Jun-01
Jul-Aug-
00
Type
Paper
Paper
Abstract
Publisher
Water Environment Re-
search Foundation
1 32 pages. Soft cover.
Water Environmental Re-
search Foundation. 2000.
282 pages.
Lakes and Reservoirs:
Research and Manage-
ment, Volume 7, Issue 3,
Page 189-199, Sep 2002
Chemosphere. 2004 Nov.,
v. 57, issue 8, p. 853-862.
Agriculture, Ecosystems
& Environment. June
2002. v. 90(1) p. 9-15.
Water Science Technol-
ogy. 2001 ;44(1 1-1 2):1 -8.
Environmental Manage-
ment 12:663-671
Journal of environmental
quality. 2003 Nov-Dec, v.
32, no. 6, p. 2436-2443.
Soil Science Society of
America journal. May/
June 2001 . v. 65 (3) p.
941 -948.
Soil Science Society of
America Journal. Jul/Aug
2000. v. 64 (4) p. 1 525-
1534.
Comments
Part of the Water Environment Research Foundation's ongoing
Watershed-Based Trading Demonstration Project, this study
tracks a watershed-based trading program in the Long Island
Sound in Connecticut, U.S.A. to help other municipalities devel-
op and implement trading programs of their own. Nitrogen ef u-
ent credit trading offers an equitable and cost-saving approach
for major point sources to meet nitrogen reduction requirements
and Total Maximum Daily Load (TMDL) limits.
Describes a program of watershed-based trading intended to
reduce phosphorus and sediment loading in selected reaches of
the Kalamazoo River in Michigan. Examines the environmental
and economic benefits of trading between point and nonpoint
sources. Identifies policy issues and technical design elements
vital to the design of a statewide water quality trading program.
Published by WERF. 2000. 282 pages. Soft cover
https://www.werf.org/acb/showdetl.cfm?st=0&st2=0&st3=0&DID
=7&Product_ID=186&DS_ID=3
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#
812
813
814
815
816
817
818
819
820
821
822
Title
In uence of hydrologic regime and
vegetation on phosphorus retention in
Everglades stormwater treatement area
wetlands
Enhancement of Nitrogen Removal in
Subsurface Flow Constructed Wetlands
Employing a 2-stage Configuration, an
Unsaturated Zone, and Recirculation
Rapid Removal of Nitrate and Sulfate in
Freshwater Wetland Sediments
Sulphate Reduction and the Removal
of Carbon and Ammonia in a Labora-
tory-scale Constructed Wetland
In uence of the redox condition dy-
namics on the removal efficiency of a
laboratory-scale constructed wetland
Denitrification enzyme activity of fringe
salt marshes in New England (USA)
Tissue nutrient signatures predict her-
baceous-wetland community responses
to nutrient availability
Simulating ow in regional wetlands
with the mod ow wetlands package
First Annual Report to the Governor
on Wisconsin Pollutant Trading Pilot
Studies
Second Annual Report to the Governor
on Wisconsin Pollutant Trading Pilot
Studies
Agricultural Nutrient Inputs to Rivers
and Groundwaters in the UK: Policy,
Environmental Management and Re-
search Needs
AAA Author
White, J.R., K.R.
Reddy and M.Z.
Moustafa
White, Kevin D.
Whitmire, S.L. and
S.K. Hamilton
Wiessner, A., U. Kap-
pelmeyer, P. Kuschk,
and M. Kastner
Wiessner, A., U. Kap-
pelmeyer, P. Kuschk,
M. and Kastner
Wigand, C., R.A.
McKinney, M.M.
Chintala, M.A.
Charpentier, and P.M.
Groffman
Willby, N.J., I.D. Pul-
ford, and T.H. Flowers
Wilsnack, M.M., D.E.
Welter, A.M. Montoya,
J.I. Restrepo, and J.
Obeysekera
Wisconsin Depart-
ment of Natural
Resources
Wisconsin Depart-
ment of Natural
Resources
Withers, PJ. and El
Lord
Pub.
Date
2004
1995
Oct-05
Nov-05
Jan-05
May-
Jun-04
Dec-01
Jun-01
Sep-98
Sep-99
Jan-02
Type
Report
Report
Report
Paper
Publisher
Hydrological Processes,
1 8, 343-355
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 59-67
Journal of Environmental
Quality, 34 (6): 2062-71 .
Nov-Dec 2005
Water Research; 39(1 9):
4643-4650. Nov 2005.
Water Research. 2005
Jan., v. 39, issue 1, p.
248-256.
Journal of Environmental
Quality. 2004 May-June,
v. 33, no. 3, p. 1144-1151.
New phytologist. Dec
2001.V. 152 (3) p. 463-
481.
Journal of the American
Water Resources Asso-
ciation/June 2001. v. 37
(3) p. 655-674.
Wisconsin Department of
Natural Resources
Wisconsin Department of
Natural Resources
Sci Total Environ. 2002
Jan 23;282-283:9-24.
PMID: 11852908
Comments
http://www.awra.org/jawra/index.html
This paper discusses agricultural nutrient inputs to rivers in the
UK through description of resent field research on nutrient loss,
the need for integrated management approaches which include
both N and P, the vulnerability of land use and adoption of safe
management options in relation to landscape characteristics
and the sensitivity of the watercourse along its reach. For P, the
identification of vulnerable zones represents a step forward to
the management of the river basin in smaller definable units,
which can provide a focus for safe management practices. This
requires a better understanding of the linkages between nutrient
sources, transport and impacts and is considered an urgent
research priority.
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823
824
825
826
827
828
829
830
831
832
833
834
835
836
Title
Nitrogen Removal from Pretreated
Wastewater in Surface Flow Wetlands
Adaptation of wastewater surface ow
wetland formulae for application in
constructed stormwater wetlands
Preliminary Preview for a Geographic
and Monitoring Program Project: A
Review of Point Source-Nonpoint
Source Ef uent Trading/Offset Systems
in Watersheds
Market-Based Solutions to Environ-
mental Problems
Market Structures for U. S. Water Qual-
ity Trading
The Structure and Practice of Water
Quality Trading Markets
Trading Research of Richard T
Woodward, Department of Agricultural
Economics Texas A&M University
Flax Pond ecosystem study: exchange
of phosphorus between as salt marsh
and the coastal waters of Long Island
Sound
Emergence patterns of Culex mosqui-
toes at an experimental constructed
treatment wetland in southern Califor-
nia
Effect of Pond Shape and Vegetation
Heterogeneity on Flow and Treatment
Performance of Constructed Wetlands
Emissions Trading: An NGO Perspec-
tive
An Evaluation of Cost and Benefits of
Structural Stormwater Best Manage-
ment Practices
The Economics of Structural Stormwa-
ter BMPs in North Carolina
Natural Systems for Wastewater Treat-
ment; Manual of Practice FD-16
AAA Author
Wittgren, Hans B. and
Scott Tobiason
Wong.T. H. F. and W
F. Geiger
Wood, Alexander and
Richard Bernknopf
Woodward, R.T
Woodward, R.T. and
R.A. Kaiser
Woodward, R.T,
R.A. Kaiser, and A.B.
Wicks
Woodward, Richard T.
Woodwell, G.M. and
D.E.Whitney
Workman, PD. and
W.E.Walton
Wbrman, Anders and
Veronika Kronnas
Worthington, Bryony
Wossink, Ada and Bill
Hunt
Wossink, Ada and Bill
Hunt
WPCF
Pub.
Date
1995
1997
2003
Feb-00
2002
2002
1977
Jun-00
Jan-06
3/16-
18/2004
Nov-05
2003
1990
Type
Paper
Invited paper
Paper
List of Publica-
tions
Presentation
Fact Sheet
Paper
Abstract
Publisher
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 69-78
Ecological Engineering
9:187-202.
Open-File Report 03-79
2003 U.S. Department of
the Interior U.S. Geologi-
cal Survey
Southern Agricultural
Economic Association,
Annual Meeting
Review of Agricultural
Economics, 2002
Journal of the American
Water Resources Asso-
ciation; 38: 967-979. 2002
Texas A&M University,
Department of Agricul-
tural Economics
Marine Biology 41:1-6.
Journal of the American
Mosquito Control Asso-
ciation. June 2000. v. 16
(2) p. 124-130.
Journal of Hydrology;
301(1-4): 123-138. Jan
2005.
Senior Campaigner,
Friends of the Earth
North Carolina Coopera-
tive Extension Service
WRRI Research Report
Number 344
Water Pollution Control
Federation, Alexandria,
VA
Comments
This is a USGS report that reviews the factors affecting the
potential for instituting watershed-based trading to improve
water quality. An overview of successful and failed programs
is provided, as is a description of an offset feasibility study for
mercury TMDLs in the Sacramento watershed. Three case
studies are reviewed; Dillon, Tar-Pamlico, Clear Creek. Optimal
conditions for water quality trading are listed and described.
http://pubs.usgs.gov/of/2003/of03-079/WoodjDFR03-79.pdf
http://agecon2.tamu.edu/people/faculty/woodward-richard/paps/
SAEA-MB.pdf
http://www.findarticles.eom/p/articles/mi qa4038/is 200208/
ai_n91 18352
http://www.inece.org/emissions/worthington.pdf
http://www2. ncsu.edu/unity /lockers/users/g/gawossin/stormwa-
terBMPFactsheet.pdf
http://www.ag-econ.ncsu.edu/faculty/wossink/outreach.html.
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837
838
839
840
841
842
843
844
845
846
847
848
849
Title
Decomposition of Emergent Macro-
phyte Roots and Rhizomes in a North-
ern Prairie Marsh
Development of a Constructed Subsur-
face- ow Wetland Simulation Model
Removal Efficiency of the Constructed
Wetland Wastewater Treatment System
at Bainikeng, Shenzhen
Estimating the Effectiveness of Vegetat-
ed Floodplains: Wetlands as Nitrate-ni-
trite and Orthophosphorus Filters
Non-Point Pollution from China's Rural
Areas and Its Countermeasures
The Nutrient Retention by Ecotone
Wetlands and their Modification for
Baiyangdian Lake Restoration
Plowing New Ground: Using Economic
Incentives to Control Water Pollution
from Agriculture
Protecting a Wildlife Refuge Through
Selenium Reductions
Nitrous oxide and methane emissions
from different soil suspensions: effect of
soil redox status
A Framework for Pollutant Trading Dur-
ing the TMDL Allocation Phase
Practical Case Studies of Actual Water
Pollutant Trading Programs. Market
Based Trading for Water & Wetlands
Optimal Trading Between Point and
Nonpoint Sources of Phosphorus in the
Chatfield Basin, Colorado
Air/Water Exchange of Mercury in the
Everglades I: The Behavior of Dis-
solved Gaseous Mercury in the Ever-
glades Nutrient Removal Project
AAA Author
Wrubleski, Dale A.,
Henry R. Murkin,
Arnold G. van der
Valk and Jeffrey W
Nelson
Wynn, Theresa Maria
and Sarah K. Liehr
Yang, Yang, Xu
Zhencheng, Hu
Kangping, Wang
Junsan and Wang
Guizhi
Yates, P. and J.M.
Sheridan
Yin, C.Q., C.F.Yang,
B.Q. Shan, G.B. Li,
and D.L.Wang
Yin, Chengqing and
Zhiwen Lan
Young, T. and C.
Congdon
Young, Terry
Yu, K.W, Z.P.Wang,
A. Vermoesen, WH.
Patrick, Jr., and O.
van Cleemput
Zaidi, A.Z., S.M.
deMonsabert, R.
EI-Farhan, and S.
Choudhury
Zander, B.
Zander, B. and K.
Little
Zhang, H. and S.E.
Ling berg
Pub.
Date
Sep-97
Feb-01
1995
May-83
2001
1995
1994
Jul-03
Jul-01
2004
7/15-
16/1996
Jun-96
2-Oct-
00
Type
Paper
PowerPoint
Conference
Paper
Case Study
Proceedings
Publisher
Aquatic Botany, Volume
58, Issue 2, September
1997, Pages 121 -134
Ecological Engineering;
16(4): 51 9-536. February
1 , 2001 .
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 31 -40
Agriculture, Ecosystems
& Environment, Volume
9, Issue 3, May 1983,
Pages 303-314
Water Science Technol-
ogy. 2001 ;44(7):1 23-8.
Water Science and Tech-
nology, Volume 32, Issue
3, 1995, Pages 159-1 67
Environmental Defense
Fund
Biology and fertility of
soils. July 2001. v. 34(1)
p. 25-30.
George Mason University,
Fairfax, VA. 2004.
U.S. EPA; Denver
Watersheds '96. Water
Environment Federation
and U.S. EPA
Science of the Total
Environment. 2000 Oct
2;259(1-3):1 23-33.
Comments
2003 National Forum on Water Quality Trading
Paper for the American Society of Agricultural Engineers Annual
Conference
http://mason.gmu.edu/~azaidi/ASAE04.pdf
http://www.epa.gov/owowwtr1/watershed/Proceed/little.html
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850
851
852
853
854
855
856
857
Title
Effects of Plants on Nitrogen/Phospho-
rus Removal in Subsurface Construct-
ed Wetlands
Sulfur: Limestone Autotrophic Deni-
trification Processes for Treatment of
Nitrate-contaminated Water: Batch
Experiments
A water chemistry assessment of
wastewater remediation in a natural
swamp
Purification Capacity of a Highly Load-
ed Laboratory Scale Tidal Flow Reed
Bed System with Ef uent Recirculation
Nitrogen retention and release in Atlan-
tic white cedar wetlands
Exploring Trading to Restore Base Flow
in the Charles River
Aspects of methane ow from sedi-
ment through emergent cattail (Typha
latifolia) plants
Review and assessment of methane
emissions from wetlands.
AAA Author
Zhang, R.S., G.H.
Li, Z. Zhou, and X.
Zhang
Zhang, Tian C. and
David G. Lampe
Zhang, X., S.E.
Feagley, J.W Day,
WH. Conner, I.D.
Hesse, J.M. Rybczyk,
andWH.Hudnall
Zhao, Y.Q., G. Sun,
and S.J. Allen
Zhu, WX. and J.G.
Ehrenfeld
Zimmerman, Robert
Yavitt, J. B. & Knapp,
A. K.
Bartlett, KB and Har-
riss, RC
Pub.
Date
Jul-05
Feb-99
Nov-
Dec-00
Sep-04
Mar-
Apr-00
Jul-03
Jul-98
1993
Type
PowerPoint
Paper
Paper
Publisher
Huan Jing Ke Xue,26(4):
83-6. July 2005
Water Research; 33(3):
599-608. February 1999.
Journal of environmental
quality. Nov/Dec 2000. v.
29(6) p. 1960-1968.
Science of The Total En-
vironment; 330(1-3): 1-8.
Sept 2004.
Journal of environmental
quality. Mar/Apr 2000. v.
29(2) p. 612-620.
New Phytologist
Volume 139 Page 495
-July 1998
doi:1 0.1 046/j. 1469-
8137.1998.00210.x
Volume 139 Issue 3
Chemosphere. Vol. 26, no.
1-4, pp. 261-320. 1993
Comments
2003 National Forum on Water Quality Trading
In this paper, the ow of methane is measured in Typha latifolia
L. (cattail)-dominated wetlands from microbial production in
anoxic sediment into, through, and out of emergent T. latifolia
shoots (i.e. plant transport). The purpose was to identify key en-
vironmental and plant factors that might affect rates of methane
ef ux from wetlands to the Earth's atmosphere.
http://www.blackwell-synergy.eom/doi/abs/1 0.1 046/j. 1469-
8137.1998.00210.x
In this report, we review progress on estimating and under-
standing both the magnitude of, and controls on, emissions of
CH sub(4) from natural wetlands. We also calculate global wet-
land CH sub(4) emissions using this extensive ux data base
and the wetland areas compiled and published by Matthews
and Fung (1987).
http://www.csa. com/pa rtners/viewrecord.php?requester=gs&coll
ection=ENV&recid=2883945
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#
858
859
860
861
862
863
864
865
866
867
868
Title
Global carbon exchange and methane
emissions from natural wetlands: Ap-
plication of a process-based model
Economic Linkages Between Coastal
Wetlands and Water Quality: A Review
of Value Estimates Reported in the
Published Literature
Using Surveys to Value Public Goods:
The Contingent Valuation Method
The economic value of wetland ser-
vices: a meta-analysis
Getting paid for stewardship: An agri-
cultural community water quality trading
guide
Nutrient Trading: Improving Water Qual-
ity Through Market-Based Incentives
Lessons About Ef uent Trading from a
Single Trade
Lessons Learned from the Trading
Pilots: Applications for Wisconsin Water
Quality Trading Policy
A Feasibility Analysis of Applying Water
quality Trading in Georgia Watersheds
Water Quality Trading in the Lower
Delaware River Basin: A Resource for
Practitioners
Trading on Water
AAA Author
Cao, Mingkui;
Marshall, Stewart;
Gregson, Keith
Kazmierczak, R.F.
Mitchell, R.C. and
R.T. Carson
Woodward, RT and
Wui.Y.
Conservation Tech-
nology Information
Center
World Resources
Institute
Woodward, R.T and
R.C. Bishop
Kranmer, J. M. and
Resource Strategies,
Inc.
gia Water Planning
and Policy Center
Institute for Environ-
mental Studies
Greenhalgh, S. and
P. Faeth
Pub.
Date
Jun-96
2001
1989
2000
2006
2004
2003
Jul-03
Jun-05
Mar-06
2001
Type
Paper
Paper
Paper
Paper
Journal Article
Paper
Working Paper
Report
Article
Publisher
Journal of Geophysical
Research, Volume 1 01 ,
Issue D9, p. 14399-14414
Unpublished Research
Paper, 22 p.
Resources for the Future,
Washington, DC p. 4-5.
Ecological Economics 37
(2001) p. 257-270.
Conservation Technology
Information Center
WRI Annual Report
2003. World Resources
Institute.
Review of Agricultural
Economics, 2003.
Resource Strategies, Inc.
Georgia Water Planning
and Policy Center
Institute for Environmen-
tal Studies
Forum for Applied Re-
search and Public Policy
Comments
This study used a methane emission model based on the
hypothesis that plant primary production and soil organic matter
decomposition act to control the supply of substrate needed by
methanogens; the rate of substrate supply and environmental
factors, in turn, control the rate of CH4 production, and the
balance between CH4 production and methanotrophic oxidation
determines the rate of CH4 emission into the atmosphere. The
model was used to calculate spatial and seasonal distributions
of CH4 emissions at a resolution of 1 ° latitudex! ° longitude. The
calculated net primary production (NPP) of wetlands ranged
from 45 g C m-2yr-1 for northern bogs to 820 g C m-2yr-1 for
tropical swamps. Sensitivity analysis showed that the response
of CH4 emission to climate change depends upon the com-
bined effects of soil carbon storage, rate of decomposition, soil
moisture and activity of methanogens.
http://adsabs.harvard.edu/cgi-bin/nph-bib query?bibcode
=1996JGR...10114399C&db key=PHY&data
type=HTML&format=
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CD
cn
#
869
870
871
872
873
874
Title
Policy Options for Reducing Phospho-
rus Loading in Lake Champlain: Final
Report to the Lake Champlain Basin
Program
Economic and Environmental Implica-
tions of Phosphorus Control at North
Bosque River (Texas) Wastewater
Plants
Implementation of the EPA 's Water
Quality Trading Policy for Storm Water
Management and Smart Growth
The Economics of Total Maximum Daily
Loads
National Forum on Synergies Between
Water Quality Trading and Wetland
Mitigation Banking
The Potential for Water Quality Trading
in Ohio
AAA Author
Winsten, J.; Green-
wood, K.; Hession,
C.; Johnstone, S.;
Jokela, W; Klein-
man, P.; Meals,
D.; Michauld, A.;
Parsons, R.; Pease,
J.; sharpley, A. and E.
Thomas
Keplinger, K.
Trauth, K.M.andYee-
Sook Shin
Keplinger, K.
Environmental Law
Institute
Sohngen, B.
Pub.
Date
2004
Jul-03
Dec-05
Feb-03
Jan-06
2005
Type
Report
Report
Journal Article
Report
Report
Publisher
Lake Champlian Basin
Program
Texas Institute for Applied
Environmental Research
Journal of Urban Plan-
ning and Development,
Volume 131, Issue 4, pp.
258-269.
Texas Institute for Applied
Environmental Research
Environmental Law
Institute
Ohio Environment Report:
Volume 3, Issue 1. OSU
Extension Program.
Comments
This report describes the processes and outcomes of the
project titled 'Developing and Assessing Policy Options for
Reducing Phosphorus Loading in Lake Champlain.' The goal
of this project was to facilitate the achievement of the long-term
P reduction goals set for Lake Champlain through the develop-
ment of innovative policy strategies for agricultural land.
The National Forum on Synergies Between Water Quality
Trading and Wetland Mitigation Banking report summarizes the
discussions from the Forum, held July 11-12, 2005, in Washing-
ton DC.
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vvEPA
United States
Environmental Protection
Agency
National Risk Management Research Laboratory
Cincinnati, OH 45268
Official Business
EPA/600/R-06/155
July 2007
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